MODUL F T 5 Gelombang 1 Waves - yuhuaphysics.com · Gelombang air, gelombang cahaya Water wave, light wave ... Dalam eksperimen interferens gelombang, dua pembesar suara diletakkan

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MODUL • Fizik TINGKATAN 5

UN

IT 1

• Menghuraikanpantulangelombangdalamsebutansuduttuju,sudutpantulan,panjanggelombang,frekuensi,lajudanarahperambatan.Describe reflection of waves in terms of the angle of incidence, angle of reflection, wavelength, frequency, speed and direction of propagation.

• Melukisrajahyangmenunjukkanpantulangelombang.Draw a diagram to show reflection of waves.

1.2 Menganalisis pantulan gelombang / Analysing reflection of waves

GelombangWaves1

• Menghuraikanapayangdimaksudkandenganpergerakangelombang.Describe what is meant by wave motion.

• Menyatakanbahawagelombangmemindahkantenagatanpamemindahkanjirim.State that waves transfer energy without transferring matter.

• Membezakanantaragelombangmelintangdangelombangmembujurdanmembericontoh-contohbagisetiapgelombang.Compare transverse and longitudinal waves and give examples for each type of wave.

• Menyatakanmaksudmukagelombang.State what is meant by a wavefront.

• Menyatakanarahperambatangelombangterhadapmukagelombang.State the direction of propagation of waves in relation to wavefronts.

• Mentakrifkan/Definei. Amplitud/Amplitude, ii. Tempoh/Period, iii. Frekuensi/Frequency,iv. PanjangGelombang/ Wavelength, v. HalajuGelombang/Wave speed.

• Melakardanmentakrifkangrafsesaran-masabagigelombang.Sketch and interpret a displacement-time graph for a wave.

• Melakardanmentakrifkangrafsesaran-jarakbagigelombang.Sketch and interpret a displacement-distance graph for a wave.

• Menjelaskanhubunganantaralaju,panjanggelombangdanfrekuensi.Clarify the relationship between speed, wavelength and frequency.

• Menyelesaikanmasalahberkaitanlaju,panjanggelombangdanfrekuensi.Solve problems involving speed, wavelength and frequency.

• Menghuraikanpelembapandalamsistemayunan.Describe damping in an oscillating system.

• Menghuraikanresonansdalamsistemayunan.Describe resonance in an oscillating system.

1.1 Memahami gelombang / Understanding waves

• Menghuraikanpembiasangelombangdalamsebutansuduttuju,sudutbiasan,panjanggelombang,frekuensi,lajudanarahperambatan.Describe refraction of waves in terms of the angle of incidence, angle of refraction, wavelength, frequency, speed and direction of propagation.

• Melukisrajahyangmenunjukkanpembiasangelombang.Draw a diagram to show refraction of waves.

1.3 Menganalisis pembiasan gelombang / Analysing refraction of waves

01-Physic F5 2015 (FSY5p).indd 25 10/15/15 3:04 PM

© Nilam Publication Sdn. Bhd. 26


UN

IT 1• Menghuraikanspektrumelektromagnet.

Describe the electromagnetic spectrum.• Menyatakancahayanampakmerupakansebahagiandaripadaspektrumelektromagnet.

State that visible light is a part of the electromagnetic spectrum.• Menyenaraikansumbergelombangelektromagnet.

List sources of electromagnetic waves.• Menghuraikanciri-cirigelombangelektromagnet.

Describe the properties of electromagnetic waves.• Menghuraikanaplikasigelombangelektromagnet.

Describe applications of electromagnetic waves.• Menghuraikankesanbahayaakibatpendedahanberlebihankepadasebahagiankomponenspektrumelektromagnet.

Describe the detrimental effects of excessive exposure to certain components of the electromagnetic spectrum.

1.7 Menganalisis gelombang elektromagnet / Analysing electromagnetic waves

• Menghuraikanpembelauangelombangterdiridaripadapanjanggelombang,frekuensi,laju,arahperambatandanbentukgelombang.Describe diffraction of waves in terms of wavelength, frequency, speed, direction of propagation and shape of waves.

• Melukisrajahyangmenunjukkanpembelauangelombang.Draw a diagram to show diffraction of waves.

1.4 Menganalisis pembelauan gelombang / Analysing diffraction of waves

• Menyatakanprinsipsuperposisi./State the principle of superposition.• Menerangkaninterferensgelombang./Explain interference of waves.• Melukiscorakinterferens./Draw interference patterns.• Menterjemahkancorakinterferens./Interpret interference patterns.

• Menyelesaikanmasalahberkaitaninterferensgelombang,λ= axD

.

Solve problems involving interference of waves, λ = axD

1.5 Menganalisis inteferens gelombang / Analysing interference of waves

• Menghuraikangelombangbunyi.Describe sound waves.

• Menjelaskanhubunganantarakenyaringandanamplitud.Explain how loudness relates to amplitude.

• Menerangkanhubanganantarakelangsingandanfrekuensi.Explain how pitch relates to frequency.

• Menghuraikanaplikasipantulangelombangbunyi.Describe applications of reflection of sound waves.

• Mengirajarakdenganmenggunakanpantulangelombangbunyi.Calculate distance using reflection of sound waves

1.6 Menganalisis gelombang bunyi / Analysing sound waves




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1 Gelombang ialah gangguan atau ayunan yang merambat melalui ruang-masa. Perambatan gelombang

menyebabkanpemindahan tenaga dan momentum darisatutitikketitikyanglain.

Wave is a disturbance or oscillation that travels through space-time. Wave motion causes transfers of energy and

momentum from one point to another.

2 Apabilatenagadipindahkanolehgelombangdaripadasumberyangbergetarkepadapenerima,makatidak

terdapatpemindahan zarah-zarah antaraduatitik.When energy is transferred by wave from a vibrating source to a distant receiver, there is no transfer of particles between the two points.

PerbandinganantaragelombangmelintangdangelombangmembujurComparison between transverse wave and longitudinal wave

GelombangmelintangTransverse waves

GelombangmembujurLongitudinal waves

TakrifDefinition

Gelombangmelintangialahgelombangdimanazarah-zarahmediumnyabergetarpadaarahyang

berserenjang denganarahperambatangelombang.Transverse waves are waves in which the direction of vibration of the particles of the medium is

perpendicular to the direction of wave propagation.

Gelombangmembujurialahgelombangyangmanazarah-zarahmediumnyabergetarpadaarah

yang selari denganarahperambatangelombang.Longitudinal waves are waves in which the direction of vibration of the particles of the medium is

parallel to the direction of wave propagation.

RajahDiagram

Tandakanarahgetaranzarahdanarahperambatangelombang.Indicate the direction of vibration of the particles and the direction of wave propagation.

Tandakanarahgetaranzarahdanarahperambatangelombang.Indicate the direction of vibration of the particles and the direction of wave propagation.

ContohExample

Gelombang air, gelombang cahaya

Water wave, light wave

Gelombang bunyi

Sound wave

ArahgetaranzarahThe direction of vibration of the particles

ArahperambatangelombangThe direction of wave propagation

C=Puncak/CrestT =Lembangan/Trough

C C

T T

C=Mampatan/CompressionR=Renggangan/Rarefaction

ArahgetaranspringDirection of the vibration of the spring

λ

JarakdarisumberDistance from source

TitikdalamfasayangsamaPoints in phase

Sesaranayunan

Dsi

plac

emen

t of o

scill

atio

n

Panjanggelombang,λWavelength, λ

AmplitudAmplitude, a

C C CR R

ArahperambatangelombangDirection of wave propagation

ArahgetaranzarahDirection of vibration of the particles

Memahami Gelombang Understanding Waves

1.1




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TerminologiTerminology

PeneranganExplanation

Panjanggelombang,λWavelength, λ

Panjanggelombangialah jarak antaradua titik yang berturutan yangbergetardalamfasayangsama.

Wavelength is the distance between two consecutive points which are vibrating in phase.atau/or

Jarakantaradua puncak berturutanatau lembangan yangberturutan.(rujukrajahdibawah.

The distance between two successive crests or two successive troughs . (refer diagram below)

Panjanggelombangialah jarak antaradua mampatan yangberturutanataujarak

antaradua renggangan yangberturutanpadagelombangbunyi.(rujukrajahdibawah)

Wavelength is the distance between two successive compressions or two successive

rarefactions in a sound wave. (refer to the diagram below)

Mukagelombang/Wavefront

TakrifDefinition

Garisanataupermukaanyangmenyambungkantitik-titikpada fasa yangsama.

The locus of points which vibrates in phase .

JenismukagelombangType of wavefront

MukagelombangmembulatMukagelombangsatahPlane wavefront Circular wavefront

PenjelasanExplanation

Arah perambatangelombangadalah berserenjang denganmukagelombang.

The direction of the propagation of a wave is perpendicular to its wavefront.


MukagelombangWavefront


MukagelombangWavefront

C=puncak/CrestT=Lembangan/Trough

MukagelombangWave front

TitikdalamfasayangsamaPoints in phase

λ

λ

C

T

λ

λ

Puncak/Crest

λ Lembangan/Trough




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Halajugelombang,vWavespeed, v

Jarak perambatan gelombang dalam satu saat.

The distance propagated by a wave in one second.

Halajugelombangbergantungpada medium dimanagelombangmerambatmenerusinya.

The wavespeed depends on the medium the waves are travelling through.

PuncakCrest

Puncakialahtitikpadagelombangdengan sesaran positif yang maksimum .

A crest is the point on a wave with the maximum positive displacement .

LembanganTrough

Lembanganialahtitikpadagelombangdengan sesaran negatif yang maksimum .

A trough is the point on a wave with the maximum negative displacement .

MampatanCompression

Ialahkawasansepanjanggelombangmembujurdimana tekanan dan ketumpatan

zarah lebih tinggi daripadatekananatmosfera.

Region along a longitudinal wave where the pressure and density of particles are

higher than atmospheric pressure.

RengganganRarefaction

Ialahkawasansepanjanggelombangmembujurdimana tekanan dan ketumpatan

zarah lebih rendah daripadatekananatmosfera.

Region along a longitudinal wave where the pressure and density of particles are

lower than atmospheric pressure.

Sistemayunan/Oscillation System

DefinisiayunanDefinition of oscillation

Ayunanialahgerakan berkala yangberulang-alikpadakedudukankeseimbangan.

Oscillation is a periodic motion performs a repeated to-and-fro motion about an equilibrium position.

JenisayunanType of oscillation

AyunanbandulringkasdangetaranspringOscillation of pendulum and vibration of spring

SatuayunanlengkapOne complete oscillation

Suatugerakanyangberulang-alikpadasatukedudukankeseimbangan.One complete oscillation is to-and-fro motion from the equilibrium position.

atau/or

Pergerakandari satu kedudukan tertentu kekedudukanlaindanbalikkekedudukanyangasal.The movement from one extreme position to the other and back to the same position.

Amplitud,aAmplitude, a

Sesaran maksimum sesuatuobjekdarikedudukankeseimbangannya.

The maximum displacement of the object from its equilibrium position.UnitS.I.:meter(m)/S.I. unit: metre (m)

Kedudukankeseimbangan

Equilibrium position

Satu ayunan lengkap

One oscillation

Satu ayunan lengkap

One oscillation




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Tempoh,TPeriod, T

Masa yang diambil bagisatuayunan lengkap .T=1f

The time taken for one complete oscillation.UnitS.I.:saat(s)/S.I. unit: second (s)

t=masa/timen=bilanganayunan/number of oscillations

T=tn

Frekuensi,fFrequency, f

Bilangan ayunanlengkap per saat .

The number of complete oscillations per second .UnitS.I.:Hertz(Hz)/The S.I. unit: Hertz (Hz)

f=nt f=

1T atau

or

GrafGraph

Grafsesaran-jarakGrafsesaran-masaDisplacement-distance graph Displacement-time graph

KedudukankeseimbanganEquilibrium position

Kedudukanobjekdimanatiada daya paduan yangbertindakkeatasnya.

The position of the object where there is no resultant force acting on it.

HalajuVelocity

Halaju, v = f λVelocity, v = f λ


Halajugelombang =frekuensi×panjanggelombang Wavespeed = frequency × wavelength v =f λ

GrafGraph

Jarak,d(cm)Distance, d (cm)

Sesaran,x(cm)Displacement, x(cm)

A

a

a

v

f

v

λ

f

λ

SesaranDisplacement

MasaTime

a

T

O

λ

a= Amplitud/Amplitude

λ= Panjang gelombang

Wavelength

a= Amplitud/Amplitude

T= Tempoh/Period

O=kedudukan keseimbangan

the equillibrium position

0 0 0

O




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InferensInference

EksperimenExperiment

1.TempohBandulRingkas Period of A Simple Pendulum

2.PanjangGelombangAir Wavelength of Water Wave

Eksperimen: 1.TempohbandulringkasExperiment: 1. Period of a simple pendulum 2.Panjanggelombangair 2. Wavelength of water wave

LampuLampMotor

Motor

BargetaranVibrating bar

StroboskopmekanikalMechanical stroboscope

AirWater

SatahgelombangairPlane water wavesKertasputih

(skrin)White paper

(screen)

KakiretortRetort stand

BenangThread

LadungPendulum bob

SenarairadasdanbahanList of apparatusand materials

SusunanradasArrangement of the apparatus

Tempoh / Masa ayunan bergantung padapanjang bandul.The period / time of oscillation depends on

the length of the pendulum.

Tempoh meningkat dengan panjang / Semakin panjang bandul ringkas, semakin panjangtempoh ayunan.The period increases with length / The longer the

pendulum, the longer the period of oscillation.

Mengkaji hubungan antara panjang dan tempoh ayunan bandul ringkas.To investigate the relationship between the length and

the period of oscillation for a simple pendulum.

Pembolehubahdimanipulasikan: Panjang, ℓ Manipulated variable: Length, ℓ Pembolehubahbergerakbalas: Tempoh ayunan, TResponding variable: Period of oscillation, T

Pembolehubahyangdimalarkan: Sudut ayunan (<10°), jisim ladungFixed variable: Small angular displacement (< 10°),

mass of pendulum bob

Jam randik, pembaris meter, kaki retort, pengapit-G dan 2 keping gabus / papan lapis.Stopwatch, metre ruler, thread, retort stand, G-clamp

and 2 small pieces of cork / plywood.

Panjang gelombang dipengaruhi oleh frekuensi.Wavelength is influenced by frequency.

Semakin tinggi frekuensi, semakin pendek panjang gelombang.The higher the frequency is, the shorter the wavelength

will be.

Mengkaji hubungan antara frekuensi dan panjang gelombang bagi gelombang.To investigate the relationship between frequency and

wavelength of a wave.

Pembolehubahdimanipulasikan: Frekuensi penggetarManipulated variable: The frequency of the vibrator

Pembolehubahbergerakbalas: Panjang gelombangResponding variable: The wavelength

Pembolehubahyangdimalarkan: Kedalaman airFixed variable: The depth of water

Tangki riak, stroboskop mekanikal, pembaris meter, motor penggetar, kertas putih, bekalan kuasa, lampu dan bar kayu.Ripple tank, mechanical stroboscope, metre ruler,

vibrator motor, white paper, power supply, lamp and

wooden bar.

PembolehubahdalameksperimenVariables inthe experiment

TujuanAim

HipotesisHypothesis




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_

t = t + t2

1 2

_

T = t 10

t = t + t2

1_

2

_

T = t 10

I/cm

λ /cm

oo f/Hz

T / 2 2s

t/s

T/sℓ/cm

90.0

80.0

70.0

60.0

50.0

40.0

2T /s2

t /s1 t /s2 t/s_

Frekuensi,f/HzFrequency, f / Hz

10

20

30

40

50

Panjanggelombang,λ/cmWavelength, λ / cm

ProsedurProcedure

PenjadualanDataTabulation of the data

MenganalisisdataAnalysis of the data

1.Radasdanbahandisediakansepertidalam rajahdenganpanjangbandulditetapkanpada 90.0cm. Apparatus and materials are set up as shown in

the diagram with the length of pendulum fixed

at 90.0 cm.

2.Hujungbandulditarikkesisidengansudut sesaranyangkecildandilepaskan. The pendulum is pulled sideways with a small

angular displacement and released.

3.Masa10ayunanlengkap,t1diukurdan

direkodkan. The time for 10 complete oscillations, t

1, is

measured and recorded.

4.Langkah(3)diulangiuntukmendapatkant2.

Step (3) is repeated to get t2.

5.Eksperimendiulangidenganℓ=80.0cm, 70.0.cm,60.0cm,50.0cmdan40.0cm. The experiment is repeated using ℓ = 80.0 cm,

70.0 cm, 60.0 cm, 50.0 cm and 40.0 cm.

6.Bacaandirekodkandan,

danT2dikira.

The readings are tabulated and ,

and T2 are calculated.

1. Tangki riak disediakan seperti dalam rajah dan sehelai kertas putih diletakkan di bawah tangki riak. A ripple tank is set up as shown and a sheet of

white paper is placed under the ripple tank.

2. Hidupkan suis motor penggetar pada frekuensi 10 Hz. Switch on the vibrator motor at a frequency of

10 Hz.

3. Perhatikan gelombang air dengan menggunakan stroboskop dan ukur panjang gelombang. Observe the water waves by using the

stroboscope and measure the wavelength.

4. Ulangi eksperimen sekurang-kurangnya empat kali dengan frekuensi motor penggetar: 20 Hz, 30 Hz,40 Hz dan 50 Hz. Repeat the experiment at least four times at the

frequencies of vibrator motor: 20 Hz, 30 Hz,

40 Hz and 50 Hz.




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1 Seorangpelajarmenggetarkansuatusistemgetaranspringsebanyak4kalipersaat.Panjanggelombangbagispringtersebutialah0.6m.Berapakahhalajugelombangmenerusispringtersebut?A student makes a spring vibrating system vibrate at 4 times per second. The wavelength of the wave on the spring is 0.6 m. What is the speed of the wave moving along the spring?Penyelesaian / Solution

2 Gelombang radio merambat dengan halaju3×108ms–1.BerapakahpanjanggelombangbagigelombangradioFMyangditerimapada200MHzbagimendapatkansiaranradiotersebut?Radio waves travel at a speed of 3 × 108 m s–1. What is the wavelength of FM radio waves received at 200 MHz on your radio dial?Penyelesaian / Solution

3 Seutas tali direntangkan di atas lantai. Satupenghujung tali tersebut digoyangkan denganfrekuensi 8 Hz. Graf di bawah menunjukkansebahagianpergerakantalidalamsuatumasa.A long rope is stretched out on the floor. One end of the rope is then shaken at frequency of 8 Hz. The graph below shows the rope at a particular moment in time.

Tentukan/Determine(a) amplitud/the amplitude(b) panjanggelombang/the wavelength(c) halajugelombang/the speedPenyelesaian / Solution

4 Rajah menunjukkan gelombang bunyi yangdihasilkandaripadasatutalabunyi.The diagram below shows the sound waves produced by a tuning fork.

(a) Berdasarkanrajah,tentukanBased on the diagram, determine

(i) amplitud/the amplitude (ii) panjanggelombang/the wavelength(b) Berapakah frekuensi gelombang bunyi

sekiranyahalajubunyiadalah330ms–1?What is the frequency of the sound waves if the speed of sound is 330 m s–1?

Penyelesaian / Solution

5 Rajahdibawahmenunjukkangrafsesaran-jarak.The diagram below shows the displacement-time graph.

Berdasarkangrafdiatas,tentukanBased on the graph above, determine the(a) amplitud/amplitude (b) tempoh/period(c) frekuensi/frequencyPenyelesaian / Solution

Diberi / Given f = 4 Hz, λ = 0.6 mv = f λ = 4 Hz × 0.6 m = 2.4 m s–1

Diberi / Given v = 3 × 108 m s–1, f = 200 MHzv = f λ (3 × 108 m s–1) = (200 × 106 Hz) x λ λ = 1.5 m

(a) a = 0.5 m(b) λ = 0.8 m(c) v = f λ = 8 Hz × 0.8 m = 6.4 m s–1

(a) (i) a = 4 cm

2

= 2 cm

(ii) 3λ = 150 cm λ = 50 cm

(b) v = f λ 330 m s–1 = f × 0.5 m f = 660 Hz

(a) a = 10 m(b) T = 0.4 s

(c) f = 1T

= 1

0.4 s

= 2.5 Hz

Sesaran/mDisplacement/m

Jarak/mDistance/m0.4 0.8 1.2 1.6

0

0.5

–0.5

4cm

150cm


Masa/sTime/s0.2 0.4 0.6 0.8

0

10

–10

...

Latihan / Exercise

KBAT




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Two types of dampingDuajenispelembapan

Grafpelembapan/A graph to show dampingAmplitud/Amplitude Sesaran/Displacement

masa/timemasa/time

PelembapanluarExternal damping

adalahdisebabkanoleh

kehilangan tenaga

untukmengatasi

daya geseran atau

rintangan udara .

the loss of energy

to overcome frictional

force or

air resistance .

PelembapandalamInternal damping

adalahdisebabkanoleh

kehilangan tenaga

kerana mampatan dan

regangan molekul dalam

sistem.

the loss of energy due to the

extension and compression

of molecules in the system.

Pelembapandalamsistemayunan/Damping in an oscillation system

Pelembapan/Damping

• Pelembapanialah pengurangan amplitud

bagisatusistemayunandimana tenaga

dilesapkandalambentuk tenaga haba .

Damping is the decrease in amplitude of an oscillating

system when energy is drained out as heat energy.

• Amplitud akansemakinberkurangdanmenjadisifar

apabila ayunan berhenti .

The amplitude will gradually decrease and become zero when the

oscillation stops .

Resonans/Resonance• Resonansberlakuapabilasuatusistem

dipaksabergetarpada frekuensi yang

samadengan frekuensi aslinya yang

disebabkanoleh daya luar Resonance occurs when a system is made to oscillate

at a frequency equivalent to its

natural frequency by an external force

• Sistemyangberesonansiniberayunpada

amplitudyang maksimum

The resonating system oscillate at its maximum amplitude.

Sistemayunan/Oscillating system

• Sistemayunanitutidakberayunberterusandengan amplitud yangsamakecualiapabilasistemituberayun

dalam vakum .The oscillating system does not continue with the same amplitude indefinitely except when the system is oscillating in a vacuum .

Mengalami/Experiences

Some effects of resonance

Beberapakesandaripadaresonans

menyebabkan/causes

• Penaladidalamradiodantelevisyendiputarkanuntukmemilihstesenprogram.Penaladalamlitardiubahsehingga

resonans tercapai,pada frekuensi daripadastesentertentuyangdipilih.Maka,

isyarat elektrik yang kuat dicapai.The tuner in a radio or television enables us to select the programmes. The circuit in the tuner is

adjusted until resonance is achieved at the frequency transmitted by a particular station

selected. Hence a strong electrical signal is produced.

• Kesanresonansjugamembawa

kemusnahan .Contohnya,jambatan

runtuhapabila amplitud getaran

bertambah yangdisebabkanoleh

resonans ,sepertiapayangtelahberlakudiTacomaNarrowsBridgediUSApada1949.Fenomenaberlakuolehtindakananginyangmenyebabkanjambatanbergetar

dengan amplitud yang besar .The effects of resonance can also cause

damage . For example, a bridge can

collapse when the amplitude of its vibration increases as a result of resonance ,

such as the Tacoma Narrows Bridge in USA in 1949. The action of the wind caused the bridge to vibrate at a

large amplitude .

• Amplitud dan tenaga berkurang

Amplitude and energy decreases

• Frekuensi malar/ Frequency is constant

t (s)

d (cm)

t (s)

a (cm)

00




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DayaluarExternal force

Daya luar mestidikenakankepadasistemayunanuntukmembolehkansistemberayun

secaraberterusan.

An external force must be applied to an oscillation system to enable the system to go on continuously.

AyunanpaksaForced oscillation

Dayaluarmembekalkan tenaga kepadasistemmemaksasistemberayun.Ayunaninidinamakanayunanpaksa.

The external force supplying energy to the system forces the oscillation. This oscillation is called a forced oscillation.

FrekuensiasliNatural frequency

Frekuensiasliialah frekuensi sesuatu sistem yang bergetar sendiri tanpasebarangdayaluaryangbertindakkeatasnya.

Natural frequency is the frequency of a system which oscillates freely without the action of an external force.

EksperimenyangmenunjukkanfenomenaresonansExperiment to show a phenomenon of resonance


• Frekuensi bandulringkasbergantungkepada panjang bandul.

The frequency of a simple pendulum depends on the length of the pendulum.• DuabandulyangmempunyaipanjangyangsamaadalahBdanD.

Two of the pendulums which have the same length are B and D.

PemerhatianObservation

• ApabilabandulBberayun,semuabandullaindipaksauntukberayun,When pendulum B oscillates, all the other pendulums are forced to oscillate,

• tetapibandulDberayundengan amplitud yang maksimum .

but pendulum D oscillates with maximum amplitude .

• Bandulyanglainakanberayundengan amplitud yang sangat kecil .

The other pendulums oscillate with very small amplitudes .

PerbincanganDiscussion

• BandulBdanbandulDmempunyaipanjangyangsama.Pendulum B and pendulum D are of the same length.

• FrekuensiB sama denganfrekuensiD.

The frequency of B is equal to the frequency of D.

• Olehitu,bandulBmenyebabkanbandulDberayundengan frekuensi aslinya .

Therefore, pendulum B causes pendulum D to oscillate at its natural frequency .

• BandulDmenerima tenaga yang lebih besar daripadabandulB,berbandingsetiapbandul

yanglain.Maka, resonans berlaku.

Pendulum D receives a bigger amount of energy from pendulum B compared to each of the other

pendulums. Hence, resonance occurs.

AB

C

D

E

F

BebanLoad

EksperimenbandulBarton/Experiment in Barton’s pendulum




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Pantulangelombang/Reflection of waves

• berlakuapabilagelombangtujuterkenapemantuldanmengubah arah perambatannya.

occurs when a incident wave strikes a reflector and undergoes a change in direction of propagation. • berlakukepadagelombangair,gelombangbunyidangelombangelektromagnet.

occurs to water waves, sound waves, light waves, and electromagnetic waves.

Ciri-ciri/Characteristics• Suduti=sudutr /Angle of i = Angle of r

• Panjang gelombang , frekuensi dan halaju

tidakberubahselepaspantulan.

Wavelength , frequency and speed do not change after reflection.

• Arah perambatangelombangberubahapabilaia

dipantulkan.

Direction of propagation of wave changes when it is reflected.

Hukumpantulan/Laws of reflection

• i = r

• Gelombang tuju, gelombang terpantul dan garis normal terletak pada satah yang sama pada sudut tegak dengan

permukaan pantulan pada titik tuju.

The incident wave, reflected wave and normal lie in the same plane which is perpendicular to the reflecting surface

at the point of incidence.

i=suduttuju (sudutdiantaragelombangtujudannormal) angle of incidence (the angle between the direction of propagation of the

incident wave and the normal)r=sudutpantulan (sudutdiantaragelombangpantulandannormal) angle of reflection (the angle between the direction of propagation of the

reflected wave and the normal)

GelombangtujuIncident wave



GelombangterpantulReflected wave


GelombangterpantulReflected wavePemantulsatah

Plane reflectorNormalNormal

Pem

antulsatah

Pla

ne r

eflec

tor

Pem

antulcekung

Con

cave

refl

ecto

rλ

λ

λ

λ λ

i r

λ



Menganalisis Pantulan Gelombang Analysing Reflection of Waves

1.2




UN

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InferensInference

Sudutpantulanbergantungpadasuduttuju.The angle of reflection depends on the angle of incidence.

HipotesisHypothesis

Sudut pantulan bertambah apabila sudut tuju bertambah.

The angle of reflection increases as the angle of incidence increases.

TujuaneksperimenAim of the experiment

Untuk mengkaji hubungan antara sudut tuju dan sudut pantulan.

To investigate the relationship between the angle of incidence and the angle of reflection.

PembolehubaheksperimenVariables in the experiment

Pembolehubahdimanipulasikan/Manipulated variable:

Sudut tuju / Angle of incidence

Pembolehubahbergerakbalas/Responding variable:

Sudut pantulan / Angle of reflection

Pembolehubahdimalarkan/Fixed variable:

Kedudukan cermin satah, frekuensi / Position of the plane mirror, frequency

SenaraibahandanradasList of materials and apparatus

Kotaksinar,cerminsatah,plastisin,proraktordankertasputihRay box, plane mirror, plasticine, protractor and white paper


ProsedurProcedure

1. Garisnormal,ONdilukispadakertasputih./A normal line, ON is drawn on the white paper.

2. Denganmenggunakanprotaktor,satusinarcahayadarikotaksinarditujukankecerminsatahpadasuduttuju,i=10°.By using the protractor, a ray of light from the ray box is directed to the plane mirror at angle of incidence, i = 10°.

3. Dengan menggunakan protraktor, sudut pantulan, r diukur.

By using the protractor, the angle of reflection ray, r is measured.

4. Langkah 2 dan 3 diulangi untuk sudut tuju yang lain, i = 20o, 30o, 40o, 50o. Steps 2 and 3 are repeated for other angles of incidence, i = 20°, 30°, 40°, 50°.

MenjadualkandataTabulate the data

i / ° 10° 20° 30° 40° 50°r / °

MenganalisisdataAnalysis the data

r / º

i / º

KotaksinarRay box

Cerminsatah/Plane mirror

Protraktor/Protractor

Kertasputih/White paper

Plastisin/Plasticine

N

Oir

0

Pantulangelombang/Reflection of waveEksperimen / Experiment




UN

IT 1

PembiasanGelombang/Refraction of waves

Definisi/Definition

Pembiasanialah perubahan arah gelombang atau

pembengkokan gelombangdisebabkanolehperubahanhalajuapabilaiabergerakdarisatumediumkemediumlain,

yangmempunyaiperbezaan ketumpatan optik atau

kedalaman .

Refraction is the change in direction of the wave when its speed changes as it moves from one medium to another, which has different

optical densities or different depths .

Ciri-cirigelombangyangterbiasCharacteristics of wave after refraction

Gelombangmempunyai frekuensi yang

samatetapiberbezapada halaju ,

panjang gelombang dan

arah perambatan

The wave has the same frequency but

different speed , wavelength and direction of propagation.

Gelombangair,gelombangbunyi,gelombangcahayadangelombangelektromagnetWater waves, sound waves, light waves and electromagnetic waves

Apabilagelombangmerambatdarisatumediummerentasisempadankemediumlainyang berbeza halaju,

gelombangyangterbiasakanmerambatdalam arah yang berbeza daripadagelombangtuju.

When a wave travelling in one medium crosses the boundary into another medium where its velocity is different , the refracted

wave will move in a different direction from that of the incident wave.

Ciri-cirigelombangCharacteristics of waves

KeadaanSituation

KawasandalamIn deep water

KawasancetekIn shallow water

HalajuSpeed lebih laju / faster lebih perlahan / slower

PanjanggelombangWavelength lebih panjang / longer lebih pendek / shorter

FrekuensiFrequency tidak berubah / unchanged tidak berubah / unchanged

Berlakupada/Occur to

DalamDeep

DalamDeep

DalamDeep

DalamDeep

DalamDeep

DalamDeep

CetekShallow

CetekShallow

CetekShallow

PembiasangelombangairRefraction of water waves

Lukiskangelombangairterbias.Draw the refracted water waves.

F F

Menganalisis Pembiasan Gelombang Analysing Refraction of Waves

1.3




UN

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Apabilasinartujumerambatdarimedium kurang

tumpat kemediumyang lebih tumpat ,

iaakan dibiaskan mendekati garisnormal.

When the light ray travels from an optically less dense

medium to an optically denser medium, it bends towards the normal.

Apabilasinartujumerambatdarimediumyang

lebih tumpat kemediumyang kurang

tumpat ,iaakan dibiaskan menjauhi garisnormal.

When the light travels from an optically denser

medium to an optically less dense medium, it bends away from the normal.

PembiasangelombangcahayaRefraction of light wave

SinartujuIncident ray Sinartuju

Incident rayUdara

Air

UdaraAir

KacaGlass

KacaGlass

i

r

SinarterbiasRefracted ray

SinarterbiasRefracted ray

i

r

KesanpembiasanEffects of refraction

PembiasangelombangairdilautRefraction of water wave at sea

PembiasangelombangbunyipadawaktumalamdanwaktusiangyangpanasEffects of refraction of a sound wave

at night and on a hot day

• Apabilagelombangairmerambatdaritengahlautkepantai,gelombang

air mengikut bentuk pantai .When water waves propagate from the sea to the beach, the water waves follow the

shape of the beach.• Inidisebabkangelombangairmerambatdarikawasanair

dalam kekawasanair cetek .

This is so because the water waves propagate from deep water to shallow water.

• Halaju dan panjang gelombang berkurangapabilagelombangairmenghampiripantaidangelombangairdibiaskan

mendekati garisnormal.

The speed and wavelength decrease as the waves approach the

beach and hence the water wave is refracted towards the normal.• Airditeluklebihtenangberbandingairditanjung.

The water in the bay is more calm compared to the water at the cape.

• Padawaktumalam,lapisanudaradibawahlebihsejukdaripadalapisanudaradiatas.At night, the air layer near the ground is cooler than the layer above.

• Gelombangbunyimerambat

lebih laju dalamudarapanasdaripadaudarasejukdisebabkanlapisan

udarapanas kurang tumpat daripadaudarasejuk.

Sound waves travel faster in warm air than in cold air because warm air is

less dense than cold air.

• Gelombangbunyi dibiaskan

mendekati bumipadawaktumalam.

Hence, sound waves are refracted

towards the earth at night.

Tanjung/Cape

PantaiBeach

TelukBay

LautSea

UdarapanasWarm air

UdarasejukCold air

Lukiskangelombangcahayaterbias.Draw the refracted light wave.




UN

IT 1

InferensInference

Sudut biasan bergantung kepada sudut tuju

The angle of refraction depends on the angle of incidence

HipotesisHypothesis

Sudut biasan bertambah apabila sudut tuju bertambah

The angle of refraction increases as the angle of incidence increases


Untuk mengkaji hubungan antara sudut tuju dan sudut biasan

To investigate the relationship between the angle of incidence and the angle of refraction



sudut tuju / angle of incidence


sudut biasan / angle of refraction


Indeks biasan / refractive index


Blokkaca,kotaksinar,kertasputih,protraktor,bekalankuasaGlass block, ray box, white paper, protractor, power supply


A

DP

Q

Oi

r

N

B

C

KotaksinarRay box

• Inidisebabkankedalamanairberkurangsecaraperlahanmerentasi

kawasantelukdan tenaga gelombangair disebarkan kekawasanyangluasberbandingkawasanberdekatandengantanjung.This is because the depth of water decreases gradually across the area of the bay

and the energy of the water wave spreads to a wider area compared to the region near the cape.

• Amplitud gelombangairditelukadalah kecil danolehituairdikawasanteluklebihtenang.

The amplitude of the water wave at the bay is low and hence the water at the bay is calm.

• Padaharipanas,permukaanbumiyangpanasmenyebabkanlapisanudarayangberdekatanpermukaannyamenjadipanas.On a hot day, the hot surface of the earth heats the layer of air near the surface.

• Inimenyebabkangelombangbunyi

dibiaskan menjauhi permukaanbumipadaharipanas.This causes sound waves to be

refracted away from the earth during hot day.

Pembiasangelombangcahaya/Refraction of light waveEksperimen / Experiment




UN

IT 1

ProsedurProcedure

1. Blokkacadiletakkandiatassehelaikertasputih.BentukbongkahkacadilakarkandiataskertasputihdandilabelkanABCD.Bongkahkacadialihkan.The glass block is placed on a piece of white paper. The outline of the sides of the glass block are traced on the white paper and labelled as ABCD. The glass block is removed.

2. Garis normal ON dilukis. Dengan menggunakan protraktor, sudut tuju diukur, i = 10°. Bongkahkacadiletakkansemuladiataslakaranitu.Alurcahayadarikotaksinarditujukanpadasudutiitu.AluryangterbiasdariCDdilukissebagaiPQ.Blokkacadialihkansemula.SatugarisanOPdilukis.The normal ON is drawn. By using a protractor, the angle of incidence is measured, i = 10°.

The glass block is placed again on its outline on the paper. A ray of light from the ray box is directed along the incidence line. The ray emerging from the side CD is drawn as line PQ. The glass block is removed again. The points O and P are joined by a line and is drawn as line OP.

3. Sudut biasan, r diukur. / The angle of refraction, r, ray is measured.

4. Eksperimen diulangi dengan sudut tuju, i = 20°, 30°, 40°, 50°.

The experiment is repeated for angles of incidence i = 20°, 30°, 40°, 50°.

MenjadualkandataTabulation of data

Suduttuju/angle of incidence, i / ° 10° 20° 30° 40° 50°Sudutbiasan/angle of refraction, r / °


InferensInference

Panjang gelombang air bergantung pada kedalaman air

The wavelength of water waves depends on the depth of water

HipotesisHypothesis

Apabila kedalaman air meningkat, maka panjang gelombang air meningkat

The wavelength of the water waves increases as the depth of water increases


Mengkaji hubungan antara kedalaman air dan panjang gelombang

To investigate the relationship between the depth of water and the wavelength of water waves



kedalaman air / depth of water


panjang gelombang / wavelength


frekuensi / frequency

SuduttujuAngle of incidencei / °

SudutbiasanAngle of refractionr / °

0

Pembiasangelombangair/Refraction of water waveEksperimen / Experiment




UN

IT 1


Tangkiriak,lampu,motor,barkayu,bekalankuasa,kertasputih,protraktor,pantulansatah,platperspek,pembaris-15cm,stroboskopmekanikal,pembarismeterRipple tank, lamp, motor, wooden bar, power supply, white paper, protractor, plane reflector, perspex plate, 15cm- ruler, mechanical stroboscope, metre rule


ProsedurProcedure

1. Kedalaman air, d, di atas permukaan perspek, diukur dengan menggunakan pembaris-15cm.

The depth of water, d, over a perspex plate, is measured by using a 15cm-ruler.

2.Bekalankuasadihidupkanuntukmenggetarkanmotorsupayagelombangsatahmerambatmerentasiplatperspek.Gelombangitudibekukandenganmenggunakanstroboskopmekanikal.The power supply is switched on to produce plane waves which propagate across the perspex plate. The waves are frozen by a mechanical stroboscope. The waves are sketched on the screen.

3. Jarak antara 11 jalur terang berturutan, x, diukur dengan menggunakan pembaris meter.

The distance between 11 successive bright bands, x, is measured by the metre ruler.

4.Panjanggelombang,λ,dikira/The wavelength λ, is calculated,λ= x10

cm

5. Eksperimen diulang 4 kali dengan menambahkan bilangan plat perspek untuk mengubah

kedalaman air di atas plat perspek.

The experiment is repeated 4 times by increasing the number of perspex plates to change the depth of the

water across the plate.


Kedalamanair/Depth of water, d / cm

Panjanggelombang/wavelength , λ / cm


KedalamanairDepth of waterd / cm

LampuLamp

MotorMotor



AirWater Platperspeks

Perspex plate

Kertasputih(skrin)White paper (screen)

Panjanggelombangwavelength λ / cm

0




UN

IT 1

1 RajahmenunjukkangelombangsatahairbergerakdarikawasanPkekawasanQyangmempunyaikedalamanberbeza.The diagram shows a plane water wave moving from one area P to another area Q of different depths.

HalajugelombangairdikawasanPialah18cms–1.BerapakahhalajugelombangairdikawasanQ?The speed of the water wave in area P is 18 cm s–1. What is the speed of the water wave in area Q?Penyelesaian Solution

Frekuensi gelombang di kawasan Q adalah bersamaan dengan frekuensi gelombang di kawasan P.Frequency of wave in region Q is the same as the frequency of wave in region P.

Oleh itu, / Hence, vQ = f λ

Q

vQ = (6 Hz) × 1.5 cm

= 9.0 cm s–1

vp = f λ

p

18 cm s–1 = f (3 cm)

\f = 6 Hz

4λp= 12 cm

λp = 12

4 cm

λp = 3 cm

8λQ = 12 cm

λQ = 12

8 cm

= 1.5 cm

Kedalaman P:Deep region P:

4λ=12cm 8λ=12cm

P Q

12cm

P

12cm

Q

Latihan / Exercise

KBAT




UN

IT 1

Definisi/Definition

Penyebaran gelombangapabilagelombangmerambatmelalui

celahan atau halangan .

The spreading of waves as they pass

through an aperture or obstacle .

Selepasbelauanberlaku/After diffraction has occured

Dimalarkan/Constant Berubah/Change

•Panjang gelombang, λ, malar

Wavelength, λ, is constant

•Frekuensi, f, malar

Frequency, f, is constant

•Halaju,v, malar

Speed, v, is constant

•Amplitud berkurang

Amplitude decreases

•Corak gelombang

Pattern of the wave

•Tenaga berkurang

Energy decreases

Rajah:Pembelauangelombangair.GelombangairlebihterbelaujikaDiagram: Diffraction of water wave. Waves are diffracted more if the (i)celahansempit/slit is narrow (ii) panjanggelombanglebihpanjang/wavelength is longer

Lukisgelombangyangterbelau./Draw the diffracted waves.Saizcelahan>λ/Size of gap > λ Sizecelahan≤λ/Size of gap ≤ λ

Halanganpanjang/Long obstacle Halanganpendek/Short obstacle

Rajah:Belauangelombangcahaya.Cahayamempunyaipanjanggelombangyang pendek .

Belauan gelombangcahayaterjadihanyapadacelahanyangmempunyailebar10–4mataukurang.

Diagram: Diffraction of light wave: Light has a very short wavelength. Diffraction of light waves occurs only for a slit with a width of 10–4 m or less.

Duarajahdibawahmenunjukkangambarfotobelauangelombangcahaya.Perhatikanbahawalebarpinggir-pinggircerahdangelapitutidakmalar./The two diagrams below show the photographs of diffraction of light waves. Notice that the bright and dark fringes are not constant in width.

Gambarfoto(i)dan(ii)menunjukkanbelauangelombangcahaya.Photographs (i) and (ii) show diffraction of light waves.

Apabilasaizcelahsemakinkecil,jalurcerahditengah-tengahsemakinlebar.When the size of the slit is getting smaller, the middle bright fringe will be wider.

Gambarfoto(i) Gambarfoto(ii)

Pembelauangelombang/Diffraction of waves

Menganalisis Belauan Gelombang Analysing Diffraction of Waves

1.4




UN

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Rajah/Diagram:

• Gelombangbunyimempunyaigelombangyang panjang .

Sound wave has a long wavelength.

• Belauan gelombangbunyimenyebabkanbunyimasihbolehdidengar

dipenjurudindingbangunan.Diffraction of sound waves enables sound to ‘go around a corner’.

PendengarListener Radio

Radio

DindingWall

InferensInference

Sudut bengkokan gelombang air bergantung kepada saiz celah

The angle of bending of the waves depends on the size of the gap

HipotesisHypothesis

Sudut bengkokan gelombang air meningkat apabila saiz celah berkurang

The angle of bending of the waves increases as the size of gap decreases


Mengkaji hubungan antara sudut bengkokan gelombang air dan saiz celah

To investigate the relationship between the angle of bending of the waves and the size of gap



saiz celah, a, / size of gap, a


sudut bengkokan gelombang air, θ° / angle of bending of the water waves, θ°


frekuensi penggetar / frequency of vibrator


Tangkiriak,lampu,motor,barkayu,bekalankuasa,kertasputih,duabatangbarbesi,pembarismeter,protraktordanstroboskopmekanikalRipple tank, lamp, motor, wooden bar, power supply, white paper, two pieces metal bar, metre rule, protractor and mechanical stroboscope


CelahanAperture slit

BarlogamMetal bar

LampuLamp

MotorMotor



AirWater


Pembelauangelombangair/Diffraction of water wavesEksperimen / Experiment




UN

IT 1

InferensInference

Lebar pinggir cerah di tengah bergantung kepada saiz celah

The width of the middle bright fringe depends on the size of the slit

HipotesisHypothesis

Lebar pinggir cerah di tengah bertambah apabila saiz celah berkurang

The width of the middle bright fringe increases as the size of the slit decreases


Mengkaji hubungan lebar pinggir cerah di tengah dengan saiz celah

To investigate the relationship between the width of the middle bright fringe and the size of the slit



saiz celah / size of slit


Lebar pinggir cerah di tengah / the width of the middle bright fringe


cahaya monokromatik (cahaya dengan satu panjang gelombang sahaja)

monochromatic light (light of one wavelength only)


Sumbercahayamonokromatik,slaidcelahtunggal,pembarismeterMonochromatic light source, single slit slide, metre rule

ProsedurProcedure

1. Dengan menggunakan pembaris meter, lebar celah diukur, a = 0.5 cm.

Bekalankuasadihidupkan.gelombangdibekukandenganmenggunakanstroboskopmekanikal.Gelombangdilakarkanpadaskrin.

By using a metre rule , the width of the slit is measured, a = 0.5 cm.

The power supply is switched on. The waves are freeze by a mechanical stroboscope. The waves are sketched on the screen.

2. Dengan menggunakan protraktor, sudut bengkokan, θ diukur. By using a protractor, the angle of bent, θ is measured.

3. Eksperimen diulang dengan menggunakan lebar celah,a = 1.0 cm, 1.5 cm, 2.0 cm dan 2.5 cm. The experiment is repeated for width of slit, a = 1.0 cm, 1.5 cm, 2.0 cm and 2.5 cm.


Saizcelah/Size of gap, a / cm 0.5 1.0 1.5 2.0 2.5

Sudutbengkokangelombangair/Angle of bending of water waves, θ / °


SaizcelahSize of gapa / cm

SudutbengkokangelombangairAngle of bending of water wavesθ / °

0

Pembelauangelombangcahaya/Diffraction of light waveEksperimen / Experiment




UN

IT 1


ProsedurProcedure

1. Lebar celah direkodkan, a = 0.2 mm. Cahaya dari sumber ditujukan ke arah celahan.

The width of the slit is recorded, a = 0.2 mm. The light beam from the source is directed towards the slit.

2. Dengan menggunakan pembaris meter, lebar pinggir cahaya di tengah, x, diukur.

By using a metre rule, measure the width of the middle bright fringe, x.

3. Eksperimen diulangi dengan menggunakan lebar celah, a = 0.4 mm, 0.6 mm, 0.8 mm dan 1.0 mm.

The experiment is repeated for widths of slit, a = 0.4 mm, 0.6 mm, 0.8 mm and 1.0 mm.

MenjadualkandataTabulate the data

Lebarcelah/Width of slit, a / mm 0.2 0.4 0.6 0.8 1.0

LebarpinggircerahtengahWidth of middle bright fringe, x / cm

MenganalisisdataAnalysis the data

CahayamonokromatikatauLASERMonochromatic lightor LASER

SlaidsatucelahSingle slit Slide

SkrinScreen

PinggirtengahcerahMiddle bright fringe

x

LebarcelahWidth of slita / mm0

LebarpinggircerahtengahWidth of middle bright fringex / cm




UN

IT 1

1 Rajahmenunjukkangelombangsatahairmendekatisatucelahsempit.The diagram shows plane water waves approaching a narrow slit.

PembengkokangelombangmeningkatapabilaThe bending of the waves increases when A saizcelahbertambah/the size of slit increasesB frekuensigelombangbertambah/the frequency of the wave increasesC panjanggelombangbertambah/the wavelength increases

2 Rajahmenunjukkancorakyangdihasilkandiatasskrinapabilacahayamonokromatikmelaluicelahan.The diagram shows the pattern formed on a screen when a monochromatic light is passed through a slit.

Antararajahberikut,yangmanakahterhasilapabilasaizcelahdikurangkan?Which of the following diagrams occurs when the size of the slit is decreased?A

B

C

D

3 Antara rajahberikut, yangmanakahmenunjukkancorakbelauancahayabagigelombangcahayaapabilacahayamonokromatikmelaluilubangpinyanghalus?Which of the following diagrams shows the patterns of diffraction of light waves when a monochoromatic light passes through a small pin hole?A

B

C

D

G GC C C

Latihan / Exercise

KBAT




UN

IT 1

INTERFERENS/INTERFERENCE

• Interferensialahkesandaripada superposisi dua gelombang dari dua sumber koheren

Interference is produced by the superposition of two waves from two coherent sources.

• Duagelombangadalahkoherenjikagelombangitumempunyai frekuensi yangsama, panjang gelombang

yangsamadandalam sefasa (fasa yang sama) .

Two waves are coherent if they have the same frequency , the same wavelength and are in phase (same phase) .

• Interferensterhasilapabiladuagelombangbertemusemasamerambatdalammediumyangsama.Interference occurs when two waves meet at a point during propagation along the same medium.

• Apabila dua gelombang bertindih, interferens akan terhasil sama ada interferens membina atau

interferens memusnah

When the two waves are superposed, interference will occur. It will either be constructive interference or destructive interference.

Prinsipsuperposisi/Principle of superposition

Prinsipsuperposisimenyatakanbahawaapabila dua gelombang merambat serentak dan bertindih pada satu titik,

hasil tambah sesaran pada titik itu adalah sama dengan hasil tambah sesaran gelombang itu secara individu

The Principle of superposition states that when two waves move simultaneously and coincide at a point, the displacement at that point is

equal to the sum of the displacements of the individual waves.

InterferensmembinaConstructive interference

• Terhasilapabila puncak atau

lembangan kedua-duagelombang(dalamfasa)bertindihmenghasilkangelombangyang

mempunyai amplitud maksimum

Occurs when the crests or troughs of both waves (same phase) coincide to produce a wave with

maximum amplitude .

InterferensmembinasaDestructive interference

• Terhasilapabila puncak satugelombang

bertindihdengan lembangan satugelombangyanglain(luarfasa)menghasilkangelombangyang

mempunyai amplitud sifar .

Occurs when the crests of one wave coincide

with the troughs of the other waves to produce a

wave with zero amplitude .

AmplitudmaksimumMaximum amplitude Amplitudsifar

Zero amplitude

Duajenisinterferens/Two types of interference

Menganalisis Interferens Gelombang Analysing Interference of Waves

1.5




UN

IT 1


PeneranganExplanation

AntinodAntinode

TitikdimanainterferensmembinaterbentukA point where constructive interference occurs

NodNode

TitikdimanainterferensmemusnahterbentukA point where destructive interference occurs

aJarakantaraduasumberkoherenDistance between two coherent sources

PanjanggelombangWavelength

xJarakantaraduagarisnod(ataugarisantinod)yangberturutanDistance between two consecutive nodal lines (or antinodal lines)

DJarakberserenjangdariduasumberketitikuntukpengukuranxPerpendicular distance from the two sources to the point of measurement of x

FormulaInterferensYoung:Young’s Interference Formula:

Rajah:/Diagram:

SumbergelombangWaves sources

PuncakCrest

LembanganTrough

S1

S2

gelombangamplitudsifar/zero amplitude wavesgelombangpuncakmaksimum/maximum crest wavesgelombanglembanganmaksimum/maximum trough waves

λ = axD

GarisantinodAntinodal line

LembanganTrough

PuncakCrestS

1

x

D

aS

2

InferensInference

Jarak antara dua garis nod yang berturutan bergantung kepada jarak antara dua sumber koheren.

The distance between two consecutive nodal lines depends on the distance between two coherent sources.

HipotesisHypothesis

Jarak antara dua garis nod berturutan bertambah apabila jarak antara dua sumber koheren

berkurang.

The distance between two consecutive nodal lines increases as the distance between two coherent sources

decreases.


Mengkaji hubungan antara 'jarak antara dua sumber koheren, a,' dan 'jarak antara dua garis

nod yang berturutan, x'.

To investigate the relationship between the 'distance, a, between two coherent sources' and the 'distance, x,

between two consecutive nodal lines'.

Garis antinod (Interferens membina)Antinodal line(Constructive interference)

Garisnod(Interferensmemusnah)Nodal line(Destructive interference)

Interferensgelombangair/Interference of water waveEksperimen / Experiment




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jarak antara dua sumber koheren, a / the distance, a, between two coherent sources


jarak antara dua garis nod yang berturutan, x / the distance, x, between two consecutive nodal lines


frekuensi penggetar, panjang gelombang / frequency of vibrator, the wavelength

Jarak antara sumber (pencelup) dan kedudukan di mana x diukur.

Distance between sources and the position where x is measured.


Tangkiriak,lampu,motor,kayubar,bekalankuasa,kertasputih,pencelupsfera,pembarismeterdanstroboskopmekanikRipple tank, lamp, motor, wooden bar, power supply, white paper, spherical dippers, metre rule and mechanical stroboscope


BayangCorakinterferensShadow of Interference patterns

PencelupDipper

Lampu/LampMotorMotor



AirWater


TangkiriakRipple tank

ProsedurProcedure

1. Dengan menggunakan pembaris meter, jarak antara dua pencelup diukur, a = 2.0 cm. By using a metre rule, the distance between two dippers, a, is set = 2.0 cm.

2. Bekalankuasadihidupkanuntukmenghasilkanduagelombangmembulatdaripencelup.Gelombangdibekukandenganmenggunakanstroboskopmekanikal.Gelombangdilakarkanpadaskrin.The power supply is switched on to produce two circular waves from the dippers. The waves are frozen by a mechanical stroboscope. The waves are sketched on the screen.

3. Dengan menggunakan pembaris meter, jarak antara dua garis nod yang berturutan, x, diukur. By using a metre rule, the distance between two consecutive nodal lines, x, is measured.

4. Eksperimen diulangi pada jarak yang berbeza antara dua pencelup, a = 4.0 cm, 6.0 cm, 8.0 cm dan 10.0 cm. The experiment is repeated with different values of the distance between two dippers, a = 4.0 cm, 6.0 cm, 8.0 cm and 10.0 cm.


a / cm 2.0 4.0 6.0 8.0 10.0

x / cm


JarakantaraduagarisnodberturutanDistance between two consecutive nodal linesx / cm

0

JarakantaraduapencelupDistance between the two dippersa / cm




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InferensInference

Jarak antara dua pinggir cerah yang berturutan bergantung kepada panjang gelombang

gelombang cahaya

The distance between two consecutive bright fringes depends on the wavelength of the light waves.

HipotesisHypothesis

Jarak antara dua pinggir cerah yang berturutan bertambah apabila panjang gelombang

gelombang cahaya bertambah

The distance between two consecutive bright fringes increases as the wavelength of the light waves increases.


Mengkaji hubungan antara panjang gelombang cahaya dan jarak antara dua pinggir cerah yang

berturutan

To investigate the relationship between the wavelength of light waves and the distance between two

consecutive bright fringes.



panjang gelombang cahaya LASER, λ

the wavelength of the LASER light waves, λPembolehubahbergerakbalas/Responding variable:

Jarak antara dua pinggir cerah berturutan, x

the distance between two consecutive bright fringes, x


jarak pemisahan antara celah, a, dan jarak antara dwicelah dan skrin, D

slit separation, a, and the distance between double slit and screen, D

SenaraibahandanradasList of apparatus and materials

SumbercahayaLASER,skrin,dwicelah,pembarismeterdanpembaris-15cmLASER light source, colour source, screen, double slit, metre ruler and 15-cm ruler

1 Dalamsatueksperimenuntukmengkaji corak interferensgelombangair, jarakantaraduapencelupsferaialah2.5cmdanjarakantaraduagarisantinodberturutanpadatitikpengukuranialah5.0cm.Berapakahpanjanggelombangbagiairjikajarakdariduapencelupketitikpengukuranituialah10.0cm?In an experiment to investigate the interference pattern of water waves, the distance between two spherical dippers is 2.5 cm and at the point of measurement, the distance between two consecutive antinodal lines is 5.0 cm. What is the wavelength of the water waves if the distance from the two dippers to the point of measurement is 10.0 cm?

PenyelesaianSolution

Diberi / Given a = 2.5 cm, x = 5.0 cm, D = 10.0 cm

λ = axD

= 2.5 cm × 5.0 cm10.0 cm

= 1.25 cm

Latihan / Exercise

Interferensgelombangcahaya/Interference of light waveEksperimen / Experiment




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ProsedurProcedure

1. SumbercahayaLASERdihidupkan.Panjanggelombang=λ,The LASER light source is switched on. Wavelength = λ,

2. Corakinterferensterbentukdiatasskrindiperhatikandandilakarkan.The interference pattern formed on the screen is observed and drawn.

3. Dengan menggunakan pembaris-15cm, jarak merentasi 6 pinggir cerah yang berturutan, L diukur.

By using a 15cm-ruler, the distance across 6 consecutive bright fringes, L is measured.

4.Jarak antara dua pinggir cerah yang berturutan dikira, x = L cm

5

The distance between two consecutive bright fringes, x = L cm5

is calculated.

5. Eksperimen diulangi dengan sumber LASER yang berbeza supaya panjang gelombang =

λ2, λ

3, λ

4 , λ

5.

The experiment is repeated with different LASER light sources so that the wavelength = λ2, λ3, λ4 , λ5.


λ / m

x / m


x

λ

1 Rajahmenunjukkancorakpinggiryangterbentukdalameksperimendwicelahapabilacahayamonokromatikdigunakan.Jarakantaracelahialah0.5mmdanskrinadalahsejauh3.0mdaridwicelahitu.The diagram shows the fringe pattern obtained in a double slit experiment when a monochromatic light is used. The double slits are 0.5 mm apart and the screen is 3.0 m away from the double slits.

1.4cm

Berapakahpanjanggelombangcahayamonokromatikitu?What is the wavelength of the monochromatic light?PenyelesaianSolution

Diberi / Given: a = 0.5 mm = 0.5 × 10–3 m D = 3.0 m

x = 1.4 cm 5

= 0.28 cm = 0.28 × 10–2 m

λ = axD

= (0.5 × 10–3 m) × (0.28 × 10–2 m)3.0 m

= 4.67 × 10–7 m

0

Latihan / Exercise

KBAT

CorakpinggirinterferensInterference fringe pattern

SkrinScreen

KawasaninterferensInterference area

SlitduacelahDouble slit

SumbercahayaLASERLASER light source

3.0mD

a




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2 Dalam eksperimen interferens cahaya yang menggunakan cahaya hijau dengan panjang gelombang5× 10–7m, jarak antara dua pinggir cerah yang terbentuk pada skrin ialah 0.4mm.Apabila eksperimendiulangidenganmenggunakancahayamonokromatik,L,jarakantaraduapinggircerahyangterbentukialah0.48mm.BerapakahpanjanggelombangcahayaL?In an experiment of light interference using green light of wavelength 5 × 10–7 m, two consecutive bright fringes formed on the screen are 0.4 mm apart. When the experiment is repeated using monochromatic light, L, two consecutive bright fringes formed are 0.48 mm apart. What is the wavelength of light L?Penyelesaian / Solution

3 Dalam eksperimen interferens dwicelah dengan cahaya biru, jarak antara skrin dan dwicelah ialah1.2mdanpisahanantaracelahialah2×10–4m.Pinggir-pinggircerahdangelapterbentukpadaskrin.Kiranilaix.(Diberi:panjanggelombangcahayabiru=4.0×10–7m).In a double-slit interference experiment with blue light the distance between the screen and double slits is 1.2 m and slit separation is 2 × 10–4 m. Bright and dark fringes are seen on the screen. Calculate x. (Given: the wavelength of blue light = 4.0 × 10–7 m).Penyelesaian / Solution

Diberi / Given D = 1.2 m, a = 2 × 10–4 m, λ=4.0 × 10–7 m

λ = axD

\x = λDa

= (4.0 × 10–7 m)(1.2 m)2 × 10–4 m

= 2.4 × 10–3 m

Diberi λHijau

= 5 × 10–7 m, x

Hijau = 4 × 10–4 m, x

L = 4.8 × 10–4 m

Dengan menggunakan λ = axD

,

λHijau

= ( aD

)(xHijau

) ("a" dan D adalah malar di sini),

\( aD

) = λ

Hijau

xHijau

(i)

Tetapi λL = ( a

D)(x

L)

\( aD

) = λ

L

xL

(ii)

Pers. (i) = Pers. (ii);

\λ

Hijau

xHijau

= λ

L

xL

\λL = (

λHijau

xHijau

)(xL)

= (5 × 10–7 m)(4 × 10–4 m)

× (4.8 × 10–4 m)

= 6.0 × 10–7 m

Given λGreen

= 5 × 10–7 m, x

Green = 4 × 10–4 m, x

L = 4.8 × 10–4 m

Using λ = aD

,

λGreen

= ( aD

)(xGreen

) (here, "a" and D are constants),

\( aD

) = λ

Green

xGreen

(i)

But λL = ( a

D)(x

L)

\( aD

) = λ

L

xL

(ii)

Equation (i) = Equation (ii);

\λ

Green

xGreen

= λ

L

xL

\λL = (

λGreen

xGreen

)(xL)

= (5 × 10–7 m)(4 × 10–4 m)

× (4.8 × 10–4 m)

= 6.0 × 10–7 m

InferensInference

Jarak antara dua kawasan bunyi kuat berturutan bergantung kepada jarak antara pendengar

dan dua pembesar suara.

The distance between two successive loud regions depends on the distance between the listener and the two

loudspeakers.

HipotesisHypothesis

Jarak antara dua kawasan bunyi kuat berturutan bertambah apabila jarak antara pendengar

dan dua pembesar suara bertambah.

The distance between two successive loud regions increases as the distance between the listener and the two

loudspeakers increases.

x

KBAT

Interferensgelombangbunyi/Interference of sound wavesEksperimen / Experiment




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IT 1


Mengkaji hubungan antara 'jarak antara pendengar dari dua pembesar suara' dengan 'jarak

antara dua kawasan bunyi kuat yang berturutan'.

To investigate the relationship between the 'distance between the listener and the two loudspeakers', and the 'distance

between two successive loud regions'.



'jarak antara pendengar dan dua pembesar suara', D.

the 'distance between the listener and the two loudspeakers', D.


jarak antara dua kawasan bunyi kuat yang berturutan, x

the distance between two successive loud regions, x


panjang gelombang bagi gelombang bunyi, jarak antara dua pembesar suara

the wavelength of sound waves, distance between the two loudspeakers


Duapembesarsuara,penjanafrekuensi-audio,dawaipenyambungdanpembarismeter,padangataugelanggangterbuka.Two loudspeakers, audio-frequency generator, connection wires and metre ruler, open court or field.


ProsedurProcedure

1. Dengan menggunakan pembaris meter, jarak antara pendengar dan pembesar suara,

D = 2.0 m, diukur.

Penjanaberfrekuensiaudiodihidupkan.Eksperimeninidijalankandigelanggangterbukasupayatiadagema.

By using a metre rule, the distance between the listener and the loudspeaker, D = 2.0 m, is measured.

The audio-frequency generator is switched on. This experiment is conducted in an open court so that there is no echo.

2. Pendengar berjalan selari dengan sisi depan meja dan jarak antara dua kawasan bunyi

kuat berturutan, x diukur.

The listener walks in a straight path parallel to the front edge of the table and the distance between

two successive loud regions, x, is measured.

3. Eksperimen diulangi pada jarak yang berbeza antara pendengar dengan pembesar suara,

D = 4.0 m, 6.0 m, 8.0 m dan 10.0 m.

The experiment is repeated with distances between the listener and the loudspeakers,

D = 4.0 m, 6.0 m, 8.0 m and 10.0 m.

PendengarListener

PembesarsuaraLoudspeaker

PembesarsuaraLoudspeaker

PenjanaberfrekuensiaudioAudio-frequency generator

D




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1 Dalameksperimen interferensgelombangbunyi, pendengarberadapada jarak5.0mdari duapembesarsuara. Jarak antara dua pembesar suara ialah 2.0 m. Pembesar suara disambungkan kepada penjanaberfrekuensiaudiountukmenghasilkangelombangbunyipadafrekuensi0.8kHz.In an experiment on the interference of sound waves, a listener is at a distance of 5.0 m from the two loudspeakers. The distance between the two loudspeakers is 2.0 m. The loudspeakers are connected to an audio-frequency generator to produce sound waves at a frequency of 0.8 kHz.

Hitungkan/Calculate(a) panjanggelombangbunyijikahalajubunyiialah320ms–1

the wavelength of the sound waves if the speed of sound is 320 m s–1

(b) jarakantaraduakawasanbunyikuatyangberturutanthe distance between two successive loud regions

PenyelesaianSolution

2 Dalameksperimeninterferensgelombang,duapembesarsuaradiletakkanpadajarak1.5mantarasatusamalain.Jarakantaraduabunyilemahyangberturutanialah6.0mdanpendengarberadapadajarak4.5mdaripembesarsuara.Berapakahpanjanggelombangbunyiyangdigunakan?In an experiment on the interference of waves, two loudspeakers are placed at a distance of 1.5 m from each other. The distance between two consecutive soft sounds is 6.0 m and the listener is at a distance of 4.5 m from the loudspeakers. What is the wavelength of the sound wave used?PenyelesaianSolution

Diberi / Given D = 5.0 m, a = 2.0 m, f = 0.8 × 103 Hz, v = 320 m s–1

(a) Dengan menggunakan formula / By using formula, v = f λ 320 m s–1 = (0.8 × 103 Hz)(λ) λ = 0.4 m

(b) Dengan menggunakan formula / By using formula, λ = axD

0.4 m = (2.0 m)(x)5.0 m

\x = 1.0 m

Diberi / Given a = 1.5 m, x = 6.0 m, D = 4.5 m

Dengan menggunakan formula / By using formula, λ = axD

λ = 1.5 m × 6.0 m 4.5 m

= 2.0 m


D / m 2.0 4.0 6.0 8.0 10.0

x / m


x

D0

Latihan / Exercise




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Ciri-ciriinterferensgelombangCharacteristics of interference of waves

FaktoryangmempengaruhicorakinterferensFactors affecting the interference pattern

• Corak interferensbergantungkepadanilai a .

The interference pattern depends on the value of a .

• Apabilaaberubah,corakinterferensturutberubah.When a changes, the interference pattern also changes.

Hubunganantaraλ,a,xdanDThe relationship between λ, a, x and D

HubunganantaraadanxRelationship between a and x• Jarakantaraduagarisnodyangberturutan,x

x berkadar songsang dengan jarak antara dua sumber, a The distance between two consecutive lines, x

x is inversely proportional to the distance between two sources, a

• x α 1a

HubunganantaraλdanxRelationship between λ and x• Jarakantaraduagarisnodyangberturutanataugarisantinodyangberturutan,x

x adalah berkadar langsung dengan panjang gelombang λThe distance x between two consecutive nodal lines or antinodal lines,

x is directly proportional to the wavelength of the wave, λ

• x α λ

HubunganantaraDdanxRelationship between D and x• Jarakantaraduagarisnodyangberturutanataugarisantinodyangberturutan,x

x adalah berkadar langsung dengan jarak, D, dari dua sumber ke titik untuk mengukur x.The distance between two consecutive nodal lines or antinodal lines, x

x is directly proportional to the distance, D, from the two sources to the point of measurement of x.

• x α D

x

D

x

λ

x

a0

0

0




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AplikasigelombangbunyiApplications of sound waves

Ciri-cirigelombangbunyiCharacteristics of sound waves

• Kelawarbergerakwaktumalamdengan

mengeluarkan gelombang bunyi yang tinggi

kelangsingannya dalamjulatultrasonik.

Bats can navigate in darkness by emitting high-pitch

sound waves in ultrasonic range.

• Dolphinmenggunakanfrekuensi ultrasonik 150kHzuntukkomunikasidanpanduarah.

Dolphin used ultrasonic frequency of 150 kHz for communication and navigation.

• Gema ultrasonik digunakanuntuk

mengesanretakanataukelemahandidalambongkahbesidanmengukurkedalamanlaut.

Ultrasonic echoes are used to detect cracks or flaws inside a metal block and also to measure the depth of the sea.

• Gelombang ultrasonik menghasilkanimejorgan-organdalamanyangmudahdisiasatdanmerupakanteknikyangmudahuntukprosedurdiagnosis.IanyalebihselamatdaripadaX-ray.

Ultrasonic imaging is a simple structural and safer technique for diagnostic procedure, compared to X-ray. It enables doctors to evaluate the structural aspects of the internal organs.

• Gelombangultrasonikyangmempunyai

keamatan yang tinggi bolehdigunakanuntuk

memecahkanketulanbatudalamginjalsebabia:High intensity ultrasonic shockwaves can be

used to break stones in kidneys because it:

(a) memancarkan alur sinar yang halus ,

can be transmitted in a very narrow beam ,

(b) boleh difokus kepada sasaran lebih tepat ,

can focus at the target more accurately ,

(c) boleh memindahkan tenaga yang besar

kerana frekuensi tinggi ,

can transfer large quantities of energy because of

high frequency ,

(d) Boleh merambat dalam jarak yang jauh .

Can travel at longer distance .

• Pakarcerminmatadantukangemasmenggunakanpembersihultrasonikuntukmembersihkancerminmatadanemas.Opticians and goldsmiths use ultrasonic cleaner to clean spectacles, jewellery and ornaments.

• Gelombangbunyiialahgelombang membujur .

Sound waves are longitudinal waves.

• Gelombangbunyidiklasifikasikansebagaigelombang

mekanikal .

Sound waves are classified as mechanical waves.

• Memerlukan medium (bahantara)untukmerambat.

Require a medium to propagate.

• DIhasilkanoleh getaran sepertigetarankonpembesarsuara,taligitardangetarantalabunyi.

Produced by vibration such as vibration of the cone-shaped diaphragm of a loudspeaker, guitar strings and tuning fork.

• Tidakbolehmerambatdalam vakum .

Cannot travel in a vacuum .

• Bunyiadalahsatubentuk tenaga yangmerambatsebagaigelombang.

Sound is a form of energy propagated as waves.

• Julatfrekuensiaudioadalah20Hz–20kHz.Frekuensi

yangkurangdaripada20Hzdipanggil infrasonik ,frekuensiyanglebihtinggidaripada20kHzdipanggil

ultrasonik .Can be generated at a wide range of frequency between 20 Hz –

20 kHz. Below 20 Hz it is called infrasound ; above 20 kHz

it is called ultrasound .

• Mampatandanrengganganbolehdihasilkanjika

terdapatbahanyangmanaboleh dimampatkan dan

direnggangkan .Compression and rarefaction can be formed if there is a material

which can be compressed and rarefied .

• Halajugelombangbunyiberbezadalamgas,cecairdanpepejal.Inidisebabkanolehperbezaandalam

kekuatan dayaantaraatom-atomdankedudukanatom-atomdalamtigakeadaantersebut.The speed of sound differs in gas, liquid and solid. This is due to

the differences in the strength of the inter atomic forces and closeness of the atoms in the three states.

• Mampatandanrengganganmerambatlebihlajudalam

medium berketumpatan tinggi .Gelombangbunyimerambatlebihlajudalamcecairdaripadadalam

gasdan paling laju dalampepejal.Compressions and rarefactions propagate faster in

denser medium. Sound travels faster in liquids than in

gases, but the fastest in solids.

Menganalisis Gelombang Bunyi Analysing Sound Waves

1.6




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• Doktorgigimenggunakan alur ultrasonik untukmenggerudidanmembersihkangigi.

Dentists use ultrasonic beams to vibrate and shake off dirt and plaque from the teeth of patients.

• Haiwansepertigajahdanbadaksumbu

berkomunikasimenggunakan infrasonik .Animals like elephants and rhinoceroses communicate using

infrasound .

• Jika bunyi gemadiukurdenganselamasa,tdanhalajugelombangbunyiialahv,makakedalaman,dbolehdihitungsepertidibawah:If the echo-sounders measure an interval of time, t, and the speed of sound wave in water is v, then the depth, d can be calculated as follows:

Jarakyangdilaluiolehisyaratyangdipantulkan=Distance travelled by pulse = speed×time2d=v×t

• Halajugelombangbunyi,v,dalammediumbolehditentukanmenggunakanrumusv=f λ.The speed of sound, v, in a medium can be determined using the formula v = f λ.

• Halajugelombangbunyitidakdipengaruhioleh

tekanan .Jikatekananatmosferaberubah,halajugelombangbunyidalamudarasentiasa

tetap .

The speed of sound is unaffected by pressure . If the atmospheric pressure changes, the speed of sound in air remains

constant .

• Halajugelombangbunyi meningkat dengan

suhu .

The speed of sound increases with temperature .• Halajugelombangbunyidipuncakgununglebih

rendah daripadahalajunyadiparaslaut

kerana suhunya dantidakdipengaruhioleh

tekanan rendah .

The speed of sound at the peak of high-altitude mountains is lower than its speed at the sea level because of

temperature and not due to the lower pressure .

PenghasilanBunyiProduction of Sound

dipengaruhioleh/affected by dipengaruhioleh/affected by

KenyaringanLoudness

KelangsinganPitch

AmplitudAmplitude

FrekuensiFrequency

Kenyaringanbunyibergantungkepada amplitud nya.

The loudness of the sound depends on its amplitude .

Kelangsinganbunyibergantungkepada frekuensi nya.

The pitch of the sound depends on its frequency .

SesaranDisplacement

MasaTime

MasaTime

MasaTime

MasaTime

SesaranDisplacement

SesaranDisplacement

SesaranDisplacement

KenyaringanrendahLoudness is low

KelangsinganrendahLow pitch

KelangsingantinggiHigh pitch

KenyaringantinggiLoudness is high

Lukiskanbentukgrafbagisetiapyangberikut.Draw the shape of graph for each of the following.

0 0 0 0

botboat

DasarLautSea Bed

d d




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AplikasigelombangbunyiApplications of sound waves

Gelombangbunyi/Sound wave

SonarSonar

Sonar adalah teknik menggunakan ultrasound untukmengesan objek di bawah air atau untuk mengukurkedalamandasarlaut.Isyaratultrasounddihantarkeluardari penghantar.Gemadari dasar laut itudikesanolehpenerima yang disambungkan kepada litar elektrikrakaman. Selang masa, t antara penghantaran danpenerimaan isyarat ultrasound selepas pantulan dari

dasarlautyangdiukur.Kedalamandasarlaut,d=v( t—2 )dimanavadalahhalajubunyidalamair.

Sonar is the technique of using ultrasound to locate underwater objects or to measure the depth of a seabed. Ultrasound signal is sent out from a transmitter. Its echo from the seabed is detected by a receiver which is connected to an electrical recording circuit. The time interval, t between the sending and receiving of the ultrasound signal after reflection from the seabed is measured. The

depth of the seabed, d = v( t—2 ) where v is the velocity of sound in

water.

KelangsinganrendahdankelangsingantinggiLow pitch and high pitch

Penjana frekuensi audio disambungkepada pembesar suara dan diletakkanberhampiransudutsatudinding.Tigaorangpelajar, A, B, danC, pula berdiri di suduthadapan. Apabila bunyi yang mempunyaikelangsingan tinggi dihasilkan, hanyapelajar C sahaja yang boleh mendengarbunyi dengan jelas. Apabila kelangsinganbunyi yang rendah dihasilkan, ketiga-tigapelajar boleh mendengar bunyi denganjelas.Kelangsinganadalahberkadar terusdengan frekuensi yang menyebabkanbunyi bernada tinggi. Kelangsingan yangtinggimempunyaifrekuensiyangtinggidan

KelawarbolehmenavigasidalamkegelapanA bat can navigate in darkness

Apabila gelombang ultrasonik yang dikeluarkan olehkelawar terkena sesuatu objek, ia dipantul kembalidan diterima oleh kelawar. Masa di antara pelepasangelombang bunyi dan penerimaan gelombangdigambarkanmembolehkankelawaruntukmenganggarkedudukanobjekdengantepat.Inimembolehkankelawarmenukarkan arahnya supaya dapat mengelakkan diridaripadaterlanggarobjekitu.When the ultrasonic waves emitted by the bat hit an object, they are reflected back and received by the bat. The time between the emission of the sound waves and reception of the reflected waves enables the bat to estimate the position of the object accurately. This enables the bat to adjust its direction to avoid knocking at the object.

GelombangyangmerambatmengikutpermukaanbumiWaves which propagate in the Earth's surface

1 Gelombangyangmerambatberdekatandenganpermukaanbumidikenalisebagaigelombangbumi.Gelombangradioyangberfrekuensirendahadalahsesuaiuntukkomunikasijarakjauhmengikutpermukaanbumi.Propagating waves near the earth's surface known as the wave of the earth. Low-frequency radio waves that are suitable for long-distance communication in accordance with the earth's surface.

2 Olehsebabjulatjarakyangdilaluinyapendek(lebihkurang100km),makastesengegantidiperlukanuntukmenerimadanmenghantarisyarat.Due to the short range of distance traversed, so a relay station is needed for receiving and transmitting the signal.

GelombangangkasaSpace wave

SatelitSatellite

IonosferaIonosphere

Gelombanglangit

Sky wave

Stesengeganti

Relay station

StesenpemancarTransmitting station

TelevisyenTelevision Radio

Radio

UHF VHF

StesensatelitbumiEarth satellite station

A B C




UN

IT 1

GelombangyangdipantulolehlapisanionosferaWaves reflected by the ionosphere1 Gelombangradioyangdapatdipantulbalikolehionosferadari

bahagianatasatmosferajikafrekuensinyakurangdaripada30MHzdikenalisebagaigelombanglangit.Gelombanginibolehmerambatmelaluisuatujarakyanglebihjauh.Radio waves can bounce off the ionosphere from the upper atmosphere if its frequency is less than 30 MHz known as sky wave. These waves can propagate through a greater distance.

2 GelombanglangitbergerakmengelilingiBumidenganpantulanantaraionosferadenganpermukaanbumi.Sky wave moves around the Earth with reflection between the ionosphere and the earth's surface.

GelombangyangmerambatmenembusiionosferaPropagating waves penetrate the ionosphere1 Jikafrekuensigelombangradiomelebihi30MHz,gelombang

itubolehmerambatmenembusiionosferakeruangangkasa.Gelombangjenisinidikenalisebagaigelombangangkasa.Gelombangangkasamerambatmengikutgarisluruskepenerimadisepanjanggarispandangandaripemancar.If the frequency of radio waves exceeding 30 MHz, the wave can penetrate the ionosphere into space. This type of wave is called as space wave. Space wave propagates in a straight line to the receiver along the line of sight of the transmitter.

2 Gegantiuntukmenerimadanmenghantarsemuagelombangkepermukaanbumiini.Range of propagation of space wave can be added via satellite. Satellite acts as a relay station for receiving and transmitting it back to the earth's surface.

PenerimaangelombangradioReceiving radio wave1 Untukmenerimaisyaratradio,kitamemerlukansebuahradio

dengansuatusistempenerimaandidalamnya.To receive radio signals, we need a radio with a reception system in it.

2 Sistempenerimaanradioberfungsimenerimagelombangradio,mengasingkanisyaratfrekuensiaudiodenganisyaratpembawadankemudianmenukarkanisyaratfrekuensiaudiobalikkepadabunyi./The function of radio reception system is to receive the radio waves, separating audio frequency signal with a carrier signal and then convert the audio frequency signals back into sound.

panjanggelombangyangpendek.Panjanggelombang yang pendek menyebabkanpembelauan berkurang dan bunyi kurangmerebakkeluar,jadihanyapelajarCbolehmendengar bunyi dengan jelas. Apabilakelangsinganrendah,frekuensigelombangrendah. Bunyi mempunyai panjanggelombangyangpanjang,maka iamudahdibelaukansupayaketiga-tigapelajarbolehmendengarbunyitersebut.An audio frequency generator is connected a speaker and placed near the corner of wall. Three students, A, B, and C, are standing at the other corner. When a pitch sound is high, only student C can hear the sound clearly. When a low pitch sound is generated, all the three students can hear the sound clearly. Pitch is directly proportional to frequency causes high pitch, high frequency. High frequency and short wavelength. Low wavelength cause less diffraction and spread out, so only student C can hear the sound clearly. When low pitch, low frequency so long wavelength. Sound can be easily diffracted, hence all the students can hear the sound.

1 Isyaratsonartelahdihantarsecaramenegakkedasarlautdarisebuahkapaldandipantulkandaridasarlautdandikesanolehmikrofon0.8sselepasdipancarkan.Jikahalajubunyidalamairialah1500ms–1,berapakahkedalamandasarlautitu?A sonar signal sent vertically downwards from a ship is reflected from the ocean floor and detected by a microphone on the keel 0.8 s after transmission. If the speed of sound in water is 1 500 m s–1, what is the depth of the ocean?PenyelesaianSolution

2d = v × t

2d = (1 500 m s–1) × (0.8 s)

d = 1 500 m s–1 × 0.8 s2

= 600 m

Latihan / Exercise




UN

IT 1

2 Seoranglelakiberdiridihadapansebuahdindingsatahyangbesarpadajarak50m.Diamenepuktangandanselamasaantara20tepukandangemanyaialah12.0s.Berapakahhalajubunyiitu?A man stands in front of a fairly large flat wall at a distance 50 m. He claps his hands and the time intervals between 20 claps and its echo is 12.0 s. What is the speed of the sound?Penyelesaian / Solution :

2d = v × t

2(50 m) = v × 12.0 s20

v = 166.67 m s–1

2 Spektrumelektromagnetialah spektrum yang berterusan ,tanpajurangantaranyadanfrekuensi

berterusandalamjulat./The electromagnetic spectrum is a continuous spectrum , with no gaps in it and the frequencies continuous in the range.

SinarultraunguUltraviolet light

CahayanampakVisible light

SinarinframerahInfrared light

GelombangmilimeterMillimeter waves

GelombangmikroMicrowaves

GelombangpendekradioShort-wave radio

GelombangpanjangradioLong-wave radio

Spektrumelektromagnet/The electromagnetic spectrum

Hz m

FrekuensiFrequency

PanjanggelombangWavelength

SinargamaGamma rays

SinarXX-rays

106

103

109

100

1012

10–3

1015

10–6

1018

10–9

1021 10–12

Panjanggelom

bang

Wav

elen

gth

Frekuensi

Fre

quen

cy

Gelom

bang

radio

Rad

io w

ave

Gelom

bang

mikro

Mic

row

aves

Cahayainfram

erah

Infr

ared

ligh

t

Cahaya

nampak

Visi

ble

light

Cahaya

ultraungu

Ultr

avio

let

light

Sinar

gama

Gam

ma

rays

SinarX

X-r

ays

1 Gelombangelektromagnetialah gelombang melintang ,yangterdiridaripada

ayunan medan elektrik dan medan magnet yangberserenjangdengansatu

samalain./Electromagnetic waves are transverse waves , consisting of oscillating electric fields

and magnetic fields which are perpendicular to each other.

Medanelektrik/Electric field

MedanmagnetMagnetic field

ArahperambatangelombangDirection of Propagation of waves

Menganalisis Gelombang Elektromagnet Analysing Electromagnetic Waves

1.7




UN

IT 1

Komponenmedanmagnetdan medan elektrik salingbergetarberserenjangantarasatusamalaindandenganarahperambatangelombang.

The magnetic field and electric field components of the wave oscillate at right angles to each other and to the direction of propagation of the wave.

Boleh dikutubkan .

Can be polarised .

Tenaga dipindahkanoleh

gelombang.Energy is transferred by the

waves.

Gelombang melintang

Transverse waves

Tidakmemerlukan medium untukmerambat.

Do not require a medium to propagate.

Tiada membawa sebarang cas

elektrik, iaitu, neutral

Electrically neutral

Bolehmerambatmelalui

vakum pada kelajuan cahaya

c = 3 × 108 m s–1

Can travel through a vacuum at the speed of light

c = 3 × 108 m s–1

Mematuhi persamaan gelombang,

c = f λ, c adalah halaju cahaya

Obey the wave equation,

c = f λ, c is velocity of light

Mempunyaifenomenayangsamaseperticahaya:Undergo the same phenomena as light:

iaitu pantulan, biasan, belauan dan interferens

reflection, refraction, diffraction and interference

Sifatgelombangelektromagnet

Properties of electromagnetic

waves

KesanburukdanaplikasigelombangelektromagnetDetrimental effects and the applications of electromagnetic waves

Jenis gelombang EMTypes of EM waves

SumberSource

AplikasiApplication

Kesan burukDetrimental effects

Gelombang radio

Radio waves

Pemancar/litarpengayunelektrikTransmitter / electrical oscillating circuit

i. Telekomunikasi(telefon)Telecommunications (telephone)

ii. Penyiaran(TVdanradio)Broadcasting (TV and radio)

iii. Komunikasidalamkapalterbang,kapaldanpeluruberpanduCommunication in aircrafts, ships and missiles

iv.DigunakandalamradioastronomiUsed in astronomy radios

DosberlebihanmenyebabkankanserdanleukimiaLarge doses of radio wave may cause cancer and leukaemia

Gelombang mikro

Microwaves

PemancargelombangmikrodanovenMicrowave transmitter, Microwave ovens

i. Radar,memasakRadar, cooking

ii. SatelitkomunikasiCommunication satellites

Katarak,kesanpadaotakCataracts, effects on the brain

Inframerah

Infrared

Objek panas

Hot objects

Alatkawalanjauh,kamera,sistemkeselamatanRemote control, camera, security systems

PemanasanmelampauOverheating




UN

IT 1

Cahaya nampak

Visible light

Matahari,objekpanas,nyalaanmentol,tiubberpendarfluorSun, hot objects, light bulbs, fluorescent tubes

i. Penglihatan, fotosintesis

dalam tumbuhan

Sight, photosynthesis in plants

ii. Fotografi/Photography

Terlalubanyakcahayamenyebabkan

kerosakan retina To much light can

damage the retina

Sinar ultraungu

Ultraviolet radiation

Objekyangsangatpanas,matahari,lampuwapmerkuriVery hot objects, the sun, mercury vapour lamps

i. Membunuhmikrob,mengesanwangkertaspalsu/Kill microbes, detecting forged bank notes

ii. Pensterilanuntukmemusnahkankuman/Sterilisation to destroy germs

iii. PenghasilanvitaminDdalamkulitProduction of vitamin D in skin

TerlalutinggidosUVyangbolehmerosakkanretinamenyebabkan

kanser kulitLarge doses of UV which can damage retina, causes

skin cancer

Sinar-X

X-rays

Tiubsinar-XX-rays tubes

i. Radioterapi,radiografiRadiotherapy, radiography

ii. Sistemkawalan/Security system

iii. • Untukmengesanretakanpadalogam./To detect cracks in metal.

• Memeriksabarangdilapanganterbang.Checking of luggage at airports.

Kerosakan sel; kanser

Cell damage; cancer

Sinar gama

Gamma rays

BahanradioaktifRadioactive substances

i. Rawatan kanser Cancer treatment

ii. PensterilanperalatanSterilisation of equipment

iii. KawalanperosakdalampertanianPest control in agriculture

iv.UntukmengesankebocoranpaipdalamtanahTo detect leckages in underground pipes

Kerosakansel;kanser

dan mutasiCell damage, cancer and

mutations

1 Graf yang manakah menunjukkan hubunganantarafrekuensi,f,dengantempoh,T,bagisuatugelombang? / Which graph shows the relationship between frequency, f and period, T, of a wave?A f

0 T

C

0

f

T

B

0

f

T

D

0

f

T

2 Rajah2menunjukkangrafsesaranmelawanjarakbagigelombang./Diagram 2 shows the displacement-distance graph of a wave.

atihan Pengukuhan / Enrichment ExerciseL

Sesaran/cmDisplacement/cm

Jarak/cmDistance/cm2 4 6 8

0

1.0

–1.0

Rajah2 Diagram 2

Pernyataanyangmanakahbetul?Which statement is correct?A Amplitudnyaialah2.0cm. The amplitude is 2.0 cm.B Panjanggelombangnyaialah4.0cm. The wavelength is 4.0 cm.C Tempohayunannyaialah4.0s. The period of oscillation is 4.0 s.D Bilanganayunandalam2sialah0.5. The number of oscillation in 2 s is 0.5.




UN

IT 1

5 Rajah 5 menunjukkan gelombang air yangmerambat ke arah satu pemantul dalam tangkiriak.Diagram 5 shows water waves propagating towards a reflector in a ripple tank.

PemantulReflector

Rajah5 Diagram 5

Corakgelombangmanakahyangbetulselepasiamenghentampemantultersebut?Which wave pattern is correct after it hits the reflector?

A

PemantulReflector

C

PemantulReflector

B

PemantulReflector

D

PemantulReflector

6 Rajah6menunjukkangelombangairyangberubaharah apabila bergerak dari kawasan cetek kekawasandalam.Diagram 6 shows water waves change direction when they move from shallow water to deep water.

Aircetek

Shallow water

AirdalamDeep water

Rajah6 Diagram 6

Apakahnamafenomenaini?What is the name of this phenomenon?A Pembiasan RefractionB Pantulan ReflectionC Belauan DiffractionD Interferens Interference

3 Antararajahberikut,yangmanakahmenunjukkancontohgelombangmembujur?Which diagram shows an example of a longitudinal wave?A Cahayabergerakdarilampukeskrin. Light traveling from a lamp to a screen.

KantaLens

LampuLamp

SkrinScreen

B Riak air disebabkan pencelup bergetar keatasdankebawah.

Water ripple caused by a dipper moving up and down.

Air

Water

PencelupDipper

C Springditolakkehadapandankebelakang. A spring is pushed forwards and backwards.

D Springditolakkeatasdankebawah. A spring is pushed up and down.

4 Rajah4menunjukkangelombangsatahmerambatmelaluikawasandengankedalamanyangberbezadidalamsebuahtangkiriak.Diagram 4 shows plane waves propagating at different depths in a ripple tank.

ArahperambatangelombangDirection of wave propagating

KawasandalamDeep area

KawasancetekShallow area

16cm 16cm

Rajah4 Diagram 4

Jika kelajuan gelombang air di kawasan dalamialah 16 cm s–1, berapakah kelajuan di kawasancetek?If the speed of water waves in the deep area is 16 cm s–1, what is its speed in the shallow area?A 7.5cms–1

B 8.0cms–1C 16.0cms–1

D 32.0cms–1




UN

IT 1

7 Rajah 7menunjukkan satu alat yang digunakanolehpengurupwanguntukmengesanwangkertaspalsu.Diagram 7 shows a device used by a money-changer to detect counterfeit bank notes.

Rajah7/Diagram 7

Jenis gelombang elektromagnet yang digunakanialahThe type of electromagnetic wave used isA gelombangmikro/microwaveB inframerah/infraredC sinarultraungu/ultraviolet rayD sinar-X/x-ray

8 Rajah8menunjukkanimejyangdiperolehseorangguru yang mengendalikan suatu aktiviti dengancahayaLASERsertaradasyanglain.Diagram 8 shows an image obtained by a teacher who conducted an activity with LASER light and other apparatus.

Rajah8/Diagram 8

RajahdiatasmenunjukkanfenomenaThe diagram above shows the phenomenon ofA pantulan/reflectionB pembiasan/refractionC pembelauan/diffractionD interferens/interference

9 Rajah9menunjukkansatucorakinterferens.Diagram 9 shows an interference pattern.

a

CrestPuncak

Source1Sumber 1

Source2Sumber 2 7.0cm

2.5cm

Rajah9/Diagram 9

Jikapanjanggelombangialah1.0cm,berapakahnilaibagijarakantaraduasumber,a?If the wavelength is 1.0 cm, then what is the value of a, the distance between the two sources?A 2.0cm C 2.8cmB 2.4cm D 3.2cm

10 Rajah10menunjukkanduadenyutangelombangdihasilkanpadaPdanQ.PdanQadalahsamajarakdariX.Diagram 10 shows two wave pulses produced at P and Q. P and Q are at the same distance from X.

aa

QX

P

Rajah10/Diagram 10

BentukgelombangyangmanakahdiperhatikandiX?/Which waveform is observed at X?

A2a

B2a

C

Da

11 Rajah 11 menunjukkan pinggir-pinggir yangdiperoleh apabila cahayahijau digunakandalameksperimendwicelahYoung.Diagram 11 shows the fringes obtained when green light is used in a Young’s double slit experiment.

Rajah11/Diagram 11

Antaraberikut,yangmanakahmerupakanpinggir-pinggir yang diperhatikan jika cahaya hijaudigantikandengancahayamerah?Which of the following fringes are observed when the green light is replaced by red light?

A

B

C




UN

IT 1

1 Rajah 1.1(a)menunjukkan sebilah gergaji berayun secaramengufuk apabila satu beban 100 g dipasangkepadanya.Rajah1.1(b)menunjukkangrafsesaran-masabagiayunanbilahgergajiitu.Diagram 1.1(a) shows a jigsaw blade oscillating horizontally when a 100 g load is fixed to it. Diagram 1.1(b) shows the displacement-time graph for the oscillating jigsaw blade.


Masa(s)Time(s)0.5 1.0 2.01.5 2.5 3.0

0

Rajah1.2(b)/Diagram 1.2 (b)Rajah1.2(a)/Diagram 1.2 (a)


Masa(s)Time(s)0.5 1.0 2.01.5 2.5 3.0

0

Rajah1.1(b)/Diagram 1.1 (b)Rajah1.1(a)/Diagram 1.1 (a)

Apit GG-clamp

Apit GG-clamp

Bilah gergajiJigsaw blade

Beban 100 g100 g load



Apit GG-clamp

Apit GG-clamp





Rajah1.2(a)menunjukkansebilahgergajiyangserupaberayunsecaramengufukapabilasatubeban400gdipasangkepadanya.Rajah1.2(b)menunjukkangrafsesaran-masabagiayunanbilahgergajiitu.Diagram 1.2(a) shows an identical jigsaw blade oscillating horizontally when a 400 g load is fixed to it. Diagram 1.2(b) shows the displacement-time graph for the oscillating jigsaw blade.

(a) Apakahyangdimaksudkandengansesaran?/What is meant by displacement?

Jarak pada arah tertentu. / Distance in a specified direction.

(b) PerhatikanRajah1.1dan1.2./Observe Diagrams 1.1 and 1.2. (i) Bandingkanjisimbebanyangdipasangpadahujungbilahgergaji.

Compare the mass of the loads fixed to the end of jigsaw blades.

Jisim beban Rajah 1.1 < Jisim beban Rajah 1.2. / Mass of loads in Diagram 1.1 < Mass of loads in Diagram 1.2.

(ii) Bandingkantempohayunan./Compare the period of oscillations.

Tempoh ayunan Rajah 1.1 < Tempoh ayunan Rajah 1.2.

The period of oscillation in Diagram 1.1 < The period of oscillation in Diagram 1.2.

(iii) Bandingkanbilanganayunandalam3saat. Compare the number of oscillations in 3 seconds.

Bilangan ayunan Rajah 1.1 > Bilangan ayunan Rajah 1.2.

Number of oscillations in Diagram 1.1 > Number of oscillations in Diagram 1.2.

(iv) Hubungkaitkanjisimbebandengantempohayunan. Relate the mass of the loads to the period of oscillation.

Apabila jisim beban meningkat, tempoh ayunan meningkat.

When the mass of the load increases, the period of oscillation increases.

(v) Hubungkaitkantempohayunandenganbilanganayunandalam3saat. Relate the period of oscillation to the number of oscillations in 3 seconds.

Tempoh ayunan kekal tidak berubah apabila bilangan ayunan meningkat.

The period of oscillation remains unchanged when the number of oscillations increases.

oalan Struktur / Structure QuestionsS




UN

IT 1

(c) (i) Apakahyangberlakukepadaamplitudayunanbilahgergajisetelahberayununtukbeberapaketika? What happens to the amplitude of the oscillation of the jigsaw blade after oscillating for some time?

Berkurang / Decreases

(ii) Berisatusebabuntukjawapandi1(c)(i). Give one reason for the answer in 1(c)(i).

Tenaga hilang ke persekitaran akibat geseran udara.

Energy is lost to surrounding due to air friction..

2 Rajah2menunjukkanspektrumbagigelombangelektromagnet.Diagram 2 shows the spectrum of electromagnetic waves.

Gelombangradio

Radio waves

Gelombangmikro

MicrowaveQ

Cahayanampak

Visible light

SinarultraunguUltraviolet

Sinar-XX-ray

SinargamaGamma ray

Rajah2/Diagram 2

(a) (i) DenganmerujukkepadaRajah2,namakansinaranQ. Based on Diagram 2, name the type of radiation Q.

Q ialah inframerah / Q is infrared

(ii) NamakansatukegunaansinaranQ. Name one application of radiation Q.

Kawalan remote.

Remote control.

(b) Bandingkanpanjanggelombangbagigelombangmikrodenganpanjanggelombangbagisinar-X. Compare the wavelength of microwave with that of X-ray.

Panjang gelombang bagi gelombang mikro lebih panjang daripada panjang gelombang sinar-X.

The wavelength of microwave is longer than that of X-ray.

(c) Namakan mana-mana satu gelombang elektromagnet yang panjang gelombangnya lebih panjangdaripadapanjanggelombangQ.

Name any one electromagnetic wave which has longer wavelength than that of Q.

Gelombang radio// gelombang mikro. / Radio wave// microwave.

(d) Namakansatukuantitifizikyangmalarbagisemuagelombangelektromagnet. Name one constant physical quantity in all electromagnetic waves.

Semua gelombang elektromagnet mempunyai laju yang sama dalam vakum.

All electromagnetic waves have the same speed in vacuum.

(e) Apakahbezanyadiantaragelombangelektromagnetdengangelombangbunyi? What is the difference between electromagnetic wave and sound wave?

Gelombang elektromagnet ialah gelombang melintang manakala gelombang bunyi ialah gelombang

membujur.

Electromagnetic wave is a transverse wave whereas sound wave is a longitudinal wave.

Atau / Or

Gelombang elektromagnet boleh merambat dalam vakum manakala gelombang bunyi tidak boleh.

Electromagnetic waves can travel in a vacuum whereas sound waves cannot.


Documents

MODUL F T 5 Gelombang 1 Waves - yuhuaphysics.com · Gelombang air, gelombang cahaya Water wave, light wave ... Dalam eksperimen interferens gelombang, dua pembesar suara diletakkan