Higher Physics Ink Exercises

(Unit 1, 2 & 3)

CfE Higher

Relationships Required for Higher Physics

2

3

Ink Exercise 1

1. A student sets up the apparatus in the diagram to measure the average acceleration of a model car as it travels from P to Q.

For one run, the following measurements were recorded along with their estimated errors:

clock 1 reading = (0.23 ± 0.01) s

clock 2 reading = (0.12 ± 0.01) s

stopwatch reading = (0.95 ± 0.20) s

length of car = (0.050 ± 0.0002) m

distance PQ = (0.30 ± 0.01) m

The measurement which gives the largest percentage error is the

A reading on clock 1 B reading on clock 2 C reading on the stopwatch D length of car E distance PQ 1

2. A car accelerates uniformly from rest and travels a distance of 60 m in 6 s.

The acceleration of the car, in ms-2

, is

A 0.83 B 3.3 C 5.0 D 10 E 20 1

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3. Consider the following three statements made by pupils about scalars and vectors.

I Scalars have direction only. II Vectors have both size and direction.

III Speed is a scalar and velocity is a vector.

Which statement(s) is/are true?

A I only B I and II only C I and III only D II and III only E I, II and III only 1

4. A stunt motorcyclist attempts to jump a river which is 5 m wide. The bank from which he will take off is 2 m higher than the bank on which he will land as shown below.

What is the minimum horizontal speed he must achieve just before take-off to avoid landing in the river?

A 2.0 ms-1

B 3.2 ms-1

C 7.9 ms

-2

D 10.0 ms-1

E 12.5 ms-1

1

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5. A ball is thrown vertically upwards from ground level. When it falls to the ground, it bounces several times before coming to rest. Which one of the following velocity-time graphs represents the motion of the ball from the instant it leaves the thrower’s hand until it hits the ground for a second time.

A

B

C

D

E

1

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6. The manufacturers of tennis balls require that the balls meet a given standard. When dropped from a certain height onto a test surface, the balls must rebound to within a limited range of heights. The ideal ball is one which, when dropped from rest from a height of 3.15m, rebounds to a height of 1.75 m as shown below.

a) Assuming air resistance is negligible, calculate (i) the speed of an ideal ball just before contact with the ground (ii) the speed of this ball just after contact with the ground. 6

b) When a ball is tested six times, the rebound heights are measured to be

1.71 m, 1.78 m, 1.72 m, 1.76 m, 1.73 m, 1.74 m

Calculate

(i) the mean value of the height of the bounce

(ii) the random error in this value. 4

(10)

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7. In an orienteering event, competitors navigate from the start to control points around a set course. Two orienteers, Andy and Paul, take place in a race in a flat area. Andy can run faster than Paul, but Paul is a better navigator.

From the start, Andy runs 700 m north (000) then 700 m south-east (135) to

arrive at the first control point. He has an average running speed of 3 ms-1

.

a) By scale drawing or otherwise, find the displacement of Andy, from the starting point, when he reaches the first control point. 3

b) Calculate the average velocity of Andy between the start and the first control point. 3

c) Paul runs directly from the start to the first control point with an average

running speed of 2.5 ms-1

. Determine the average velocity of Paul. 2

d) Paul leaves the starting point 5 minutes after Andy.

Show by calculation who is first to arrive at this control point. 3

(11)

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8. a) A sports car is being tested along a straight track.

(i) In the first test, the car starts from rest and has a constant

acceleration of 4.0 ms-2

in a straight line for 7.0 s.

Calculate the distance the car travels in 7.0 s. 3

(ii) In a second test, the car again starts from rest and accelerates at

4.0 ms-2

over twice the distance covered in the first test. What is the increase in the final speed of the car at the end of the second test compared with the speed at the end of the first test. 4

(iii) In a third test, the car reaches a speed of 40 ms-1

. It then

decelerates at 2.5 ms-2

until it comes to rest. Calculate the distance travelled by the car while it decelerates to

rest. 3

b) A student measures the acceleration of a trolley as it moves freely down a sloping track.

The trolley has a card mounted on it. As it moves down the track the card cuts off the light at each of the light gates in turn. Both the light gates are connected to the computer which is used for timing.

The student uses a stopclock to measure the time it takes the trolley to move from the first light gate to the second light gate.

(i) List all of the measurements that have to be made by the student and the computer to allow the acceleration of the trolley to be calculated. 2

(ii) Explain fully how each of these measurements is used in

calculating the acceleration of the trolley as it moves down the

slope. 2

(14)

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Ink Exercise 2

1. A force of 15 N acts on a box as shown below.

Which entry in the following table correctly shows the horizontal and vertical components of the force?

Horizontal component Vertical component

(N) (N)

A 15 sin 60° 15 sin 30°

B 15 cos 60° 15 sin 30°

C 15 sin 60° 15 cos 60°

D 15 cos 30° 15 sin 30°

E 15 cos 60° 15 sin 60°

1

2. A block of weight 1500 N is dragged along a horizontal road at constant speed by a force of 500 N.

What is the frictional force between the block and the road?

A 3 N B 500 N C 1000 N D 1500 N E 2000 N 1

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3. A block of wood, of mass 2.0 kg, slides with a constant velocity down a slope. The slope makes an angle of 30° with the horizontal as shown in the diagram.

What is the value of the force of friction acting on the block.

A 1.0 N B 1.7 N C 9.8 N D 17.0 N E 19.6 N 1

4. A car of mass 900 kg pulls a caravan of mass 400 kg along a straight

horizontal road with an acceleration of 2 ms-2

.

Assuming that the frictional forces are negligible, the tension in the coupling between the car and caravan is

A 400 N B 500 N C 800 N D 1800 N E 2600 N 1

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5. Two identical metal spheres X and Y are dropped onto a horizontal surface. The distance Y falls is double the distance X falls.

Which of the following is/are true if the effects of air resistance are negligible?

I Y takes twice as long to fall as X.

II The maximum speed of Y is double the maximum speed of X. III The maximum kinetic energy of Y is double that of X.

A I only B II only C III only D I and II only E I, II and III only 1

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6. a) A hot air balloon, of total mass 500 kg, is held stationary by a single vertical rope.

(i) Draw a sketch of the balloon. On your sketch, mark and label all the

forces acting on the balloon. (HINT: The upwards force on the balloon is called “Buoyancy Force”) 2

(ii) When the rope is released, the balloon initially accelerates vertically

upwards at 1.5 ms-2

. Find the magnitude of the buoyancy force. 3

(iii) Calculate the tension in the rope before it is released. 3

b) An identical balloon is moored using two ropes, each of which makes an angle of 25° to the vertical, as shown below.

By using a scale diagram, or otherwise, calculate the tension in each rope. 3

(11)

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7. During a test on car safety, two cars are crashed together on a test track.

a) Car A, which has a mass of 1200 kg and is moving at 18.0 ms-1

,

approaches car B, which has a mass of 1000 kg and is moving at 10.8 ms-1

, in the opposite direction. The cars collide head on, lock together and move off in the direction of

car A.

(i) Calculate the speed of the cars immediately after the collision. 3

(ii) Show by calculation that this collision is inelastic. 3

b) During a second safety test, a dummy in a car is used to demonstrate the effects of a collision. During the collision, the head of the dummy strikes the dashboard at 20 ms

-1 as shown below and comes to rest in 0.02 s. The mass of the

head is 5 kg.

(i) Calculate the average force exerted by the dashboard on the head of

the dummy during the collision. 3

(ii) The test on the dummy is repeated with an airbag which inflates during the collision. During the collision, the head of the dummy again travels forward

at 20 ms-1

and is brought to rest by the airbag.

Explain why there is less risk of damage to the head of the dummy

when the airbag is used. 1

(10)

40

8. A child on a sledge slides down a slope which is at an angle of 20° to the horizontal as shown below.

The combined weight of the child and the slope is 400 N. The frictional force acting on the sledge and child at the start of the slide is 20.0 N.

a) (i) Calculate the component of the combined weight of the child and sledge down the slope. 3

(ii) Calculate the initial acceleration of the sledge and child. 3

b) The child decides to start the slide from further up the slope. Explain whether or not this has any effect on the initial acceleration. 1

(7)

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9. A student performs an experiment to study the motion of the school lift as it moves upwards.

The student stands on bathroom scales during the lift’s journey upwards. The student records the reading on the scales at different parts of the lift’s journey as follows.

Part of journey Reading on scales

At the start (lift accelerating) 678 N

In the middle (steady speed) 588 N

At the end (lift decelerating) 498 N

a) Show that the mass of the student is 60 kg. 3

b) Calculate the initial acceleration of the lift. 3

c) Calculate the deceleration of the lift. 1

d) During the journey, the lift accelerates for 1.0 s, moves at a steady speed for 3.0 s and decelerates for a further 1.0 s before coming to rest. Sketch the acceleration-time graph for this journey. 2

(9)

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Ink Exercise 3

1. An aeroplane is flying at 160 ms-1

in level flight 80 m above the ground. It releases a package at a horizontal distance X from the target T.

The effect of air resistance can be neglected and the acceleration due to

gravity can be taken at 10 ms-2

. The package will score a direct hit on target t if X is

A 40 m B 160 m C 320 m D 640 m E 2560 m 1

2. The siren on a fire engine has a frequency of 260 Hz. The fire engine is moving away from a stationary observer at 36 km h

-1. The frequency heard by

the observer is

A 235 Hz B 253 Hz C 260 Hz D 268 Hz E 291 Hz 1

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3. The distance between the Earth and the Moon is 3.84 x 108 m. The mass of

the Earth is 5.98 x 1024

kg and the mass of the moon is 7.35 x 1022

kg. The gravitational force between the Earth and the Moon is

A 2.74 x 10-3 N B 1.99 x 1020 N C 7.63 x 1028 N D 2.98 x 1030 N E 1.14 x 1039 N 1

4. A pupil makes the following statements about a star receding from Earth.

I The light from a star will be red shifted. II The light from the star will be shifted to a higher wavelength. III The light from the star is shifted to a lower frequency.

Which statement(s) is/are correct?

A I only B II only C III only D I and II only E I, II and III only 1

5. A starship at rest is 12 m long. The starship then travels past a stationary observer at 0.8c. How long does the starship appear to be to the observer when in motion.

A 7.2 m B 12 m C 13.5 m D 16.4 m E 15.2 m 1

6. The universe has constantly cooled down as it expands. The temperature of the universe can be calculated by measuring the peak wavelength of background

A Infra Red B Radio waves C Ultra Violet D Microwaves

E X – rays 1

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7. The fairway on a golf course is in two horizontal parts separated by a steep bank as shown below.

A golf ball at point O is given an initial velocity of 41.7 ms-1

at 36° to the horizontal.

The ball reaches a maximum vertical height at point P above the upper fairway. Point P is 19.6 m above the upper fairway as shown. The ball hits the ground at point Q. The effect of air friction on the ball may be neglected.

a) Calculate

(i) the horizontal component of the initial velocity of the ball; 1

(ii) the vertical component of the initial velocity of the ball. 1

b) Show that the time taken for the ball to travel from point O to point Q is 4.5 s. 4

c) Calculate the horizontal distance travelled by the ball. 3

(9)

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8. A Russian Soyuz rocket has launched from French Guiana to put six satellites in orbit. One satellite, Pleiades-1, is designed to produce pictures that resolve features on the ground as small as 50 cm across.

Lift-off occurred on schedule at 23.03 local time, Friday 16 December 2011 with Pleiades-1 being dropped off in its 700 km high polar orbit some 55 minutes later. The 970 kg satellite is the result of a near-decade-long programme in the French space agency (CNES) to develop one of the most powerful Earth observation systems in the world.

(Mass of the Earth = 5.98 x 1024

kg) (Radius of Earth = 6371 km)

a) State Newton’s Law of Gravitation. 1

b) Calculate the size of the gravitational force on the satellite in its orbit. 3

c) Calculate the size of the gravitational field strength in this orbit. 3

(7) 9. A starship 20 m long is travelling at a constant speed of 0·95 c. The spacecraft

travels at this speed for 2 days, as measured by a clock on the Earth.

a) Calculate how many days have passed, as measured by a clock in the starship. 3

b) Calculate the distance travelled by the starship as measured by an observer on the starship in metres. 3

c) Calculate the length of the starship as observed by a person on earth, as it travels at 0.95c. 3

(9)

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10. In ‘Star Trek’ the spaceship U.S.S. Enterprise travels at 0.25c using impulse power. The spaceship is 725 m long.

a) Calculate what length a stationary observer on the planet Vulcan would view the ship to be. 3

b) The ship emits a light flare of wavelength 500 nm. What wavelength would the stationary observer view when the ship was moving away

from them at 2.0 x107 m s-1 ? 4

c) The crew of the U.S.S. Enterprise observe a galaxy receding from the ship at 2.5 x106 ms-1. Calculate how far away from the ship the galaxy is. 3 (10)

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Ink Exercise 4

1. The diagram below shows the screen and the settings of an oscilloscope, which is being used to measure the output frequency of a signal generator.

What is the frequency of the signal applied to the input of the oscilloscope?

A 2.5 Hz B 12.5 Hz C 40 Hz D 250 Hz E 500 Hz 1

2. The farad is the unit of capacitance. Which of the following units is equivalent to the farad?

A CV-1

B JC-1

C AV

-1

D Js-2

E Cs-1

1

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3. A battery has an e.m.f. of 6.0 V and an internal resistance of 2.0 . It is connected to a 10.0 resistor, as shown below.

The p.d. across the 10.0 resistor is

A 1.0 V B 1.2 V C 4.8 V D 5.0 V E 6.0 V 1

4. The energy stored in a capacitor, of capacitance C, when holding a charge Q is given by

A ½ QC B ½ Q/C2 C ½ Q2/C D ½ QC2

E ½ Q2C 1

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5. In the following circuit, the p.d. across the 16 resistor is 40 V when switch S is open.

The p.d. across the 16.0 resistor when switch S is closed is

A 12 V B 15 V C 30 V D 45 V E 48 V 1

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6. The following circuit is set up to investigate the charging of a capacitor.

At the start of the experiment the capacitor is uncharged.

a) The graph below shows how the p.d. VC across the capacitor varies with time from the instant the switch S is closed.

Sketch a graph showing how the p.d. VR across the resistor varies with time

during the first 10 s of charging. 2

b) Calculate the current in the circuit at the instant the p.d. across the capacitor is 6.0 V. 3

c) (i) When the capacitor is fully charged, it is removed from the circuit and

connected across a 10 resistor.

What is the total energy dissipated in the resistor? 3

(ii) In another experiment, the fully charged capacitor is connected across a 20 resistor instead of the 10 resistor.

How does the energy dissipated in this resistor compare with that calculated in part (i)?

You must justify your answer. 1

(9)

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7. The circuit below includes a cell with an e.m.f. of 1.60 V and internal resistance r.

The following readings are taken from the meters.

reading on the ammeter = 0.04 A

reading on the voltmeter, V1 = 1.20 V

reading on the voltmeter, V2 = 0.30 V

a) Calculate the value of the lost volts in the circuit. 1

b) Calculate the internal resistance, r, of the cell. 3

c) (i) The resistance of the variable resistor is altered so that the reading on the ammeter is 0.02 A. What is the resistance of the variable resistor now? 3

(ii) The resistance, R, of the variable resistor is now decreased. What effect

has this on the terminal potential difference, Vtpd, of the cell? You must justify your answer. 2

(9)

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8. A capacitor is connected across a variable frequency supply as shown in the circuit below. The output of the supply has constant amplitude.

At a certain frequency, the current in the circuit is 200 mA r.m.s. Calculate the value of the peak current in the circuit. (3)

9. In an experiment to measure the capacitance of a capacitor, a student sets up the following circuit.

When the switch is in position X, the capacitor charges up the supply voltage,

VS. When the switch is in position Y, the coulombmeter indicates the charge stored by the capacitor.

The student records the following measurements and uncertainties.

Reading on voltmeter = (2.56 ± 0.01) V

Reading on coulombmeter = (3.2 ± 0.1) C

Calculate the value of the capacitance and the percentage uncertainty in this value. You must give the answer in the form

value ± percentage uncertainty

(5)

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10. The circuit below is used to determine the internal resistance r of a battery of e.m.f. E.

The variable resistor provides known values of resistor R. For each value of resistance R, the switch S is closed and the current I is noted. For each current, the value of 1/I is calculated.

In one such experiment, the following graph of R against 1/I is obtained.

a) Conservation of energy applied to the complete circuit gives the following relationship.

E = I(R + r)

Show that this relationship can be written in the form

R = (E/I) – r 1

b) Use information from the graph to find:

(i) the internal resistance of the battery; 1

(ii) the e.m.f. of the battery. 3

(5)

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Ink Exercise 5

1. Certain materials can be “doped” to make a semiconductor called an n-type material.

In an n-type material,

A the majority charge carriers are electrons B the majority charge carriers are neutrons C the majority charge carriers are protons D there are more electrons than protons

E there are more electrons than neutrons 1

2. A student reads the following passage in a physics dictionary.

“….a solid state device in which positive and negative charge carriers are produced by the action of light on a p-n junction.”

The passage describes a

A light emitting diode B laser C capacitor D photodiode E thermistor 1

3. A crystal of silicon is “doped” with arsenic, that is, a small number of the silicon atoms are replaced with arsenic atoms.

The effect of the doping on the crystal is to

A make it into a photodiode B make it into an insulator C increase its resistance D decrease its resistance

E allow it to conduct in only one direction 1

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4. Which of the following statements is/are true?

I In a light emitting diode, positive and negative charge carriers recombine

to emit light.

II In a p-n junction diode, the majority carriers in the p-type material are electrons.

III In a photodiode, electron-hole pairs are produced by the action of light.

A I only B I and II only C I and III only D II and III only E I, II and III 1

5. Which one of the following graphs shows the relationship between the current I in a p-n Junction diode and the voltage across the diode.

A B

C D

E

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6. The circuit below shows a photodiode connected in series with a resistor and an ammeter. The power supply has an output voltage of 5V and negligible internal resistance.

In a darkened room, there is no current in the circuit. When light strikes the photodiode, there is a current in the circuit.

a) (i) Describe the effect of light on the material of which the photodiode is made. 1

(ii) In which mode is the photodiode operating. 1

(iii) The intensity of the light at the junction of the photodiode increases. Describe and explain what happens to the current in the circuit. 2

b) Light of a constant intensity is shone on the photodiode in the circuit shown above. The following measurements are obtained with S open and then with S closed.

(i) What is the value of the e.m.f. produced by the photodiode for this

light intensity? 1

(ii) Calculate the internal resistance of the photodiode for this light

intensity. 3

c) In the circuit above, the 20 resistor is now replaced with a 2 resistor. The intensity of the light is unchanged. The following measurements are obtained.

Explain why the reading on the voltmeter, when S is closed, is smaller than

the corresponding reading in part (b). 2

(10)

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7. The diagram below represents the p-n junction of a light emitting diode (LED).

a) Draw a diagram showing the above p-n junction connected to a battery so that the junction is forward biased. 1

b) When the junction is forward biased, there is a current in the diode. Describe the movement of the charge carriers which produces this

current. 2

c) Describe how the charge carriers in the light emitting diode enable light to be produced. 2

d) The following graph shows the variation of current with voltage for a diode when it is forward biased.

(i) What is the minimum voltage required for the diode to conduct? 1

(ii) What happens to the resistance of the diode as the voltage is increased above this minimum value?

Use information from the graph to justify your answer. 3

(9)

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8. a) Materials may be classified as “conductors”, “semiconductors” and “insulators”. Give an example of a material from each of these groups. 1

b) An electronics textbook states that

“….p-type semiconductor material is formed by doping a pure

semiconductor material with impurity atoms.”

What is meant by the term “n-type” semiconductor material? 2

(3)

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Ink Exercise 6

1. Hadrons are composite particles made of quarks. Up (u) quarks have a charge of + ⅔ e whilst down (d) quarks have a charge of - ⅓ e, where e is equal to the magnitude of an electron’s charge. Antiquarks have the opposite charge to these values. Which line in the following table of data on hadrons is correct?

Hadron

Quark Charge (e)

structure

A Proton udd +1

B Proton ddd +1

C Neutron uū 0

D Neutron uud +1

E Neutron udd 0 1

2. Two parallel metal plates X and Y in a vacuum have a potential difference V across them.

An electron of charge e and mass m, initially at rest, is released from plate X. The speed of the electron when it reaches plate Y is given by

A 2eV/m B √(2eV/m) C √(2V/em) D 2V/em E 2mV/e 1

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3. The diagram below shows a circuit with a 6.0 V battery connected to two parallel metal plates A and B which are 0.30 m apart.

The amount of work needed to move 2 C of charge from plate A to B is

A 1.8 J B 3.0 J C 6.0 J D 12.0 J E 20.0 J 1

4. Which row in the table shows an example of a hadron, lepton and boson?

1

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5. A particle accelerator increases the speed of protons by accelerating them between a pair of parallel metal plates, A and B, connected to a power supply as shown below.

The potential difference between A and B is 25 kV.

a) Show that the kinetic energy gained by a proton between plates A and B

is 4.0 x 10-15

J 3

b) The kinetic energy of a proton at plate A is 1.3 x 10-16

J. Calculate the velocity of the proton on reaching plate B. 4

c) The plates are separated by a distance of 1.2 m. Calculate the force produced by the particle accelerator on a proton as it travels between plates A and B. 3

d) Protons can be detected by their deflection in a magnetic field. Copy and complete the diagram below, showing clearly the path of a proton as it passes into the magnetic field. 1

Direction of

proton

+ + + + +

+ + + + + + + + + +

+ + + + +

(11)

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6. Sub-atomic particles can be either hadrons or leptons.

a) State one difference between these two groups of particles. 1

b) Give an example of a hadron and an example of a lepton. 2

c) Hadrons can be further divided into two groups. Name these two groups and state a difference between them. 3

d) A conversation is overheard between two young pupils who are discussing their science lessons.

Pupil A “We learned in science today that the nucleus of an atom is made of protons which are positively charged and neutrons which have no charge.”

Pupil B “That’s interesting because we learned in science that like charges repel. How come the protons in the nucleus don’t fly apart?”

Pupil A “I don’t know.”

Write a paragraph that would explain to the pupils why the protons in a

nucleus do not fly apart. 2

(8)

7. In a famous experiment to investigate the structure of the atom, a beam of radiation is directed at a thin, gold foil target as shown in the diagram below.

The experiment shows that most of the radiation passes through the gold foil but some “bounces back” without passing through the foil.

a) State the type of radiation used. 1

b) Explain how the results of the experiment suggest that the mass of the atom is concentrated at its centre. 2

(3)

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Ink Exercise 7

1. To demonstrate the photoelectric effect, radiation is directed onto the surface of a clean charged zinc plate. Which of the following sets of conditions is required to produce the emission of photoelectrons from the zinc plate?

1

2. An element X emits an alpha particle to form a new element. Which of the following statements is/are correct about this new element?

I The total number of protons and neutrons is 4 less than in element X. II The number of protons is the same as element X. III The new element is an isotope of element X.

A I only B II only I only C III only D I and III only E II and III only 1

3. The minimum energy required to eject an electron from a certain metal is

3.0 x 10-19

J. Light of frequency 4.8 X 1014

Hz is incident on this metal.

Which of the following statements is correct?

A Electrons will not be ejected from the metal. B Electrons will be ejected with 0 J of kinetic energy. C Electrons will be ejected with 1.8 x 10-20 J of kinetic energy. D Electrons will be ejected with 3.2 x 10-19 J of kinetic energy. E Electrons will be ejected with 6.2 x 10-19 J of kinetic energy. 1

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4. Ultraviolet radiation is incident on a zinc plate. Photoelectrons with a certain maximum kinetic energy are released from the zinc. The irradiance of the ultraviolet radiation is now increased. What happens to the maximum kinetic energy of the photoelectrons and the rate at which they are released?

1

5. The three statements below refer to the fission process.

I Fission may be spontaneous.

II Fission can be produced when neutrons bombard a nucleus, which has a large mass number.

III When fission occurs, a nucleus with a large mass number may split

into nuclei with smaller mass numbers, along with several neutrons.

Which statements is/are true?

A III only B I only II only C I and III only D II and III only E I, II and III 1

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6. It is quoted in a text book that

“the work function of caesium is 3.04 x 10-19

J”

a) Explain what is meant by the above statement. 1

b) In an experiment to investigate the photoelectric effect, a glass vacuum tube is arranged as shown below.

The tube has two electrodes, one of which is coated with

caesium. Light of frequency 6.1 x 1014

Hz is shone on to the caesium coated electrode.

(i) Calculate the maximum kinetic energy of a photoelectron leaving the

caesium coated electrode. 3

(ii) An electron leaves the caesium coated electrode with this maximum kinetic energy. Calculate its kinetic energy as it reaches the upper electrode when the

p.d. across the electrodes is 0.8 V. 4

c) The polarity of the supply voltage is now reversed.

Calculate the minimum voltage which should be supplied across the

electrodes to stop photoelectrons from reaching the upper electrode. 3

(11)

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7. The following statement represents a nuclear reaction which may form the basis of a nuclear power station of the future.

a) State the name given to the above type of nuclear reaction. 1

b) Explain, using E = mc2, how this nuclear reaction results in the production

of energy. 2

c) Using the information given below, and any other data required from the Data Sheet, calculate the energy released in the above nuclear reaction.

4

d) Calculate how many reactions of the type represented above would occur each second to produce a power of 25 MW. 3

(10)

8. The first three stages in a radioactive decay series are shown below.

a) What particle is emitted when Thorium (Th) decays to Palladium (Pa)? 1

b) How many neutrons are in the nuclide represented by ? 1

c) In the next stage of the above decay series, an alpha particle is emitted. Copy and complete this stage of the radioactivity decay series shown below, giving values for a, b, c and d, and renaming the element X.

3

(5)

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9. The apparatus shown below is used to investigate photoelectric emission from the metal surface, X, when electromagnetic radiation is shone on the surface. The frequency of the electromagnetic radiation can be varied.

a) When radiation of a certain frequency is shone on the metal surface X, a reading is obtained on the ammeter.

Sketch a graph to show how the current in the circuit varies with the

irradiance of the radiation. 2

b) Explain why there is no reading on the ammeter when the frequency of the

radiation is decreased below a particular value. 2

(4)

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Ink Exercise 8

1. Light of frequency 6 x 1014 Hz passes from air to glass. The refractive index of the glass is 1.5 and the speed of light is 3 x 10 8 ms-1. The wavelength of this light in the glass is

A 5.0 x 10-9 m B 3.3 x 10-7 m C 5.0 x 10-7 m D 7.5 x 10-7 m

E 1.8 x 1023 m 1

2. A space probe is positioned 3 x 1011

m from the Sun. It needs solar panels with an area of 4 m

2 to absorb sufficient energy from the Sun to keep it

functioning correctly.

What area of solar panels would be needed to keep the probe functioning

correctly if it is to be repositioned at a distance of 6 x 1011

m from the Sun?

A 1 m2

B 2 m2

C 4 m2

D 8 m2

E 16 m2

1

3. Which row in the following table gives the approximate wavelengths of red, green and blue light in nanometres?

1

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4. The diagram below shows some of the energy levels for the hydrogen atom.

The highest frequency of radiation emitted due to a transition between two of these energy levels is

A 2.04 x 1020 Hz B 1.63 x 1020 Hz C 3.08 x 1015 Hz D 2.46 x 1015 Hz

E 1.59 x 1014 Hz 1

5. A microwave transmitter is directed at a metal plate which has two slits P and Q in it as shown. The microwave radiation emitted has a wavelength of 3 cm.

A microwave receiver is moved from R to S and, in doing so, detects maxima and minima of intensity at the positions shown. What is the path difference between PR and QR?

A 1.5 cm

B 3.0 cm

C 4.5 cm

D 6.0 cm

E 9.0 cm 1

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6. A pupil finds a glass prism of the shape shown below when she dismantles an old optical instrument.

To investigate the optical properties of the prism, she directs a narrow beam of red light towards the prism as shown. The glass has a refractive index of 1.52 for this red light.

a) Calculate the value of the critical angle for this light in the glass prism. 3

b) On graph paper, draw the prism with the dimensions stated in the

diagram. On your diagram, show the passage of the light beam until after it emerges from the prism. Mark all relevant angles. 3

c) A second beam of light, parallel to the first and of the same wavelength,

is now directed onto the prism at A. Add to your diagram the complete path of this beam through the prism. 2

(8)

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7. A biologist is studying the effect of different colours of light on a sample of chlorophyll. The biologist sets up the apparatus shown below, using a diffraction grating

with 6.0 x 105

lines per metre to produce a first order spectrum of sunlight.

a) Explain briefly how a diffraction grating produces a continuous spectrum from the ray of sunlight. 2

b) (i) The wavelength of the light at the end X of the spectrum is 410 nm.

Calculate the value of the angle . 3

(ii) The angle A, in the diagram above, is 9°. Calculate the wavelength at end Y of the spectrum. 4

c) The biologist now uses a triangular glass prism to produce a continuous spectrum from a ray of sunlight. State two differences between this spectrum and the spectrum produced by the grating. 2

(11)

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8. The line emission spectrum of hydrogen has four lines in the visible spectrum as shown in the following diagram.

These four lines are caused by the electron transitions in a hydrogen atom

from high energy levels to a low energy level E2 as shown below.

a) From the information above, state which spectral line W, X, Y or Z is

produced by an electron transition from E3 to E2. 1

b) Explain why lines Y and Z in the line emission spectrum are brighter than the other two lines. 1

c) Infrared radiation of frequency 7.48 x 1013

Hz is emitted from a hydrogen atom.

(i) Calculate the energy of one photon of this radiation. 3

(ii) Show by calculation which electron transition produces this

radiation. 2

(7)

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9. Two identical loudspeakers X and Y are set up in a room which has been designed to eliminate the reflection of sound. The loudspeakers are connected to the same signal generator as shown.

a) When a sound level meter is moved from P to T, maxima and minima of sound intensity are detected. Explain, in terms of waves, why the maxima and minima are produced. 2

b) The sound level meter detects a maximum at P.

As the sound level meter is moved from P, it detects a minimum then a maximum then another minimum when it reaches Q.

Calculate the wavelength of the sound used. 3

(5)

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