Edexcel IGCSE Section 2 Electricity

1

Section 2: Electricity

2005 June

Q2: The circuit below contains a 1.5V dry cell, an ammeter and a thermistor at room temperature.

(a) At room temperature, the resistance of the thermistor is 1000 . Calculate the current, in amps. ...................................................................................................................................... ...................................................................... Current = .......................... A (3) (b) What happens to the resistance of the thermistor as its temperature increases? ......................................................................................................................................(1) (c) What happens to the current as the temperature of the thermistor increases? ......................................................................................................................................(1)

(Total 5 marks)

Khalid Mazhar Qureshi www.edexcel-cie.com

2

Answer


3

Q4:

(a) A metal filament lamp is switched on. Complete the boxes to show the energy transfer that occurs.

(3)

(b) The lamp is rated at 100W and is left on for 30 seconds. How much energy, in joules, is transferred to the lamp? ...................................................................................................................................... ...................................................................................................................................... Energy transferred = ........................ J (2) (c) The lamp is only 5% efficient. What does this mean? ...................................................................................................................................... ......................................................................................................................................(2) (Total 7 marks)


4

Answer


5

Q10: (a) The drawing shows an electrical circuit containing a cell, a lamp and some insulated copper wire with clips.

(i) A direct current passes through the circuit. Name the particles that flow. ............................................................................................................................... Why do the particles flow from the negative terminal to the positive terminal? ............................................................................................................................... ............................................................................................................................... (2) (ii) The circuit has a 1.5 V cell. Complete the sentence by adding the names of the two missing units. A volt is a .................................................... per .................................................... (1) (b) A student has a reading lantern. It contains a 1.5 V rechargeable battery. The lantern uses solar cells to charge its battery during the day. The student switches on the lantern at night to read. Use the relationship E = V x I x t to calculate the average current from the battery when it delivers 216 J in 2.0 hours. Show how you get your answer and include the unit. ...................................................................................................................................... ...................................................................................................................................... ................................................... Average current = .............................. (3) (Total 6 marks)


6

Answer


7

2005 Nov

Q2: A student holds a rod and charges it by friction using a cloth.

Insulator Conductor Cloth Rod (b) Explain in terms of electrons how the rod and cloth become charged as shown.

...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... (2)

(c)

A small positively-charged plastic sphere is placed at A. (i) State the direction in which the sphere moves. ............................................................................................................................... (1) (ii) Explain your answer. ............................................................................................................................... (1)

(Total 6 marks)


8

Answer

(a) insulator

insulator zero if both boxes ticked for one row

1 1

(b) 1 mark each for any two (electrons) move from the cloth to the rod electrons are negative(ly charged)

(c) (i)

to the rod / right 1

(c) (ii)

positive /similar charges repel or opposite / unlike charges attract

1

Total 6 marks


9

Q7: In the series circuit below, a lamp is lit to full brightness by direct current from a 1.5 V cell.

(a) State two differences between mains electricity and that supplied by the 1.5 V cell. 1 ................................................................................................................................... 2 ...................................................................................................................................(2) (b) Draw a parallel circuit using the 1.5 V cell to show how two lamps could be switched on and off independently and lit to full brightness.

(2) (Total 4 marks)


10

Answer

(a)1 a.c. not cell is d.c. 1 (a)2 larger voltage 1

(b) lamps in parallel with cell each lamp can be switched off/on independently

1 1

Total 4 marks


11

Q11: A torch uses three cells to light a bulb. The voltage across the bulb is 4.5 V and the current in it is 1.5 A. (a) Calculate the power input, in watts, to the torch bulb. ...................................................................................................................................... ...................................................................................................................................... Power = ...............................W

(2) (b) Use the equation energy transferred = current xvoltage xtime to calculate the energy, in joules, transferred to the bulb when the torch is used for ten minutes. ...................................................................................................................................... ...................................................................................................................................... Energy = ...................................... J

(2) (c) The filament in the torch bulb is made of tungsten which is a metal. (i) Describe the nature and direction of the current in the filament. ............................................................................................................................... ............................................................................................................................... ...............................................................................................................................

(2) (ii) The filament has a high resistance. What is the effect of the current in the filament? Explain this. ............................................................................................................................... ............................................................................................................................... ...............................................................................................................................

(2)

(Total 8 marks)


12

Answer

(a) either 6.75 (W) (2) or power = current x voltage (1)

or power = 1.5 x 4.5 2

(b) either 4050 (J) (2) or clear indication that time is 10 x 60 / = 600 (s) (1)

2

(c) flow/movement of electrons (1) from negative (end/side) to positive (end/side) (1)

2

(d) any two, (1) each collisions between electrons and ions/atoms/nuclei/other particles transfer of energy (large) rise in temperature light /infra-red (radiation) given out

do not credit molecules or gets (much) hotter

2

Total 8 marks Total 8 marks


13

2007 June

Q2: A student connects a series circuit as shown.

(a) (i) The switch is closed. Name two components in the circuit, other than the lamp,

which affect the size of the current.

1 .............................................................................................................................

2 ............................................................................................................................. (2)

(ii) The current is 0.40 A. Calculate the charge that flows during a time of 20 s.

...............................................................................................................................

...............................................................................................................................

Charge = ................................C (2)

(b) You are asked to connect a second lamp so that each lamp can be switched on and off

independently. Show, by drawing on the circuit above, how this can be done. (2)

(Total 6 marks)


14

Answer

Question No.

Acceptable Ans. Extra Info. Marks

a(i) resistor/resistance/rheostat power supply/battery/cell

1 1

a(ii) = 0.4 20 = 8 (C)

1 1

b lamp in parallel switch in series with second

lamp

1 1


15

2007 Nov

Q2: A circuit contains a resistor R, a thermistor and a buzzer connected to a cell as shown. The

circuit can be used as a simple fire alarm.

(a) (i) Complete the sentence.

When temperature increases, the resistance of a thermistor ........................................ (1)

(ii) What happens to the current in the circuit when the temperature increases?

............................................................................................................................... (1)

(b) (i) State the equation which relates voltage, current and resistance.

............................................................................................................................... (1)

(ii) When temperature increases, does the voltage across R stay the same, increase or

decrease?

............................................................................................................................... (1)

(iii) Explain your answer.

...............................................................................................................................

............................................................................................................................... (2)

(c) The buzzer starts to sound when the voltage across R is a particular value. Add a

voltmeter to the circuit diagram to show how this voltage is measured. (1)

(Total 7 marks)


16

Answer

Question No.

Acceptable Ans. Reject Marks

2(a) (i) decreases (1) (ii) increases (1) Notes (ii) e.c.f

2

2b (i) V = I x R (1) (ii) Increases (1) not dop no ecf (iii) R same (1) I bigger (1) Notes (iii) potential divider idea can score 2

4

2c voltmeter connected in parallel across buzzer or R

1


17

Q9: The diagram shows an electrical circuit.

(a) Complete the sentence.

The .................................... across the lamp is the energy transferred per

unit .................................... passing through the lamp. (2)

(b) Complete the table to show what each abbreviation represents in the equation

Q = I x t

One has been done for you.

Abbreviation Representation

Q

I

t time

(2)

(Total 4 marks)


18

Answer

Question No.


9a voltage / potential difference / pd (1) charge (1)

2

9b charge (1) current (1)

2


19

Q13: The diagram shows a 9 V battery.

(a) The battery contains six cells connected in series.

Calculate the voltage of each cell.

......................................................................................................................................

Voltage = .............................. V (1)

(b) Complete the sentence.

Current is the rate of flow of ........................................................................................ (1)

(c) The battery supplies an average current of 0.20 A for 3.0 hours. Use the equation

energy transferred = current voltage time to calculate how much energy the battery transfers during this time and give its unit.

......................................................................................................................................

......................................................................................................................................

Energy = .................................. (3)

(d) Describe the nature of an electric current in a metal wire.

......................................................................................................................................

...................................................................................................................................... (2)

(e) The battery is described as a 9 V d.c. supply.

State what the letters d.c. stand for.

...................................................................................................................................... (1)

(f) State two differences between a mains supply and the supply from the battery.

1 ...................................................................................................................................

2 ................................................................................................................................... (2)

(Total 10 marks)


20

Answer

Question No.


13a 1.5 (V) do not credit just 9 6

1

13b charge / electrons / ions 1 13c 19 440 (2) or (energy =) 0.2 x 9 x

3 60 x 60 (1) joules/J (1) note 5.4 J is (2) 3240 J is (2) 324 J is (2)

3

13d flow/movement of (free) electrons (1) from negative to positive (1) or through lattice of ions / charged atoms

2

13e direct current 1 13f ANY TWO (1 each)

mains supply is alternating current (1) or mains is a.c. mains supply is at a (much) higher voltage / 230 V (1) supply from battery is limited/battery has to be replaced/recharged

2


21

2008 june

Q3: A student connects a light dependent resistor (LDR) to a battery.

(a) The current in the LDR is 0.050 A and its resistance is 90 in the dark.

(i) State the equation which relates current, resistance and voltage.

...............................................................................................................................

............................................................................................................................... (1)

(ii) Calculate the voltage across the LDR. Show your working and give the unit.

...............................................................................................................................

...............................................................................................................................

Voltage = .................................................. (2)

(b) The LDR is moved to a position in the light.

Choose words from the box to complete the table.

You may use each word once, more than once or not at all.

Decrease Increase Stay same

Effects on . It will

the resistance of the LDR

Current in the LDR

(2)

(Total 5 marks)


22

Answer

Question No.

Correct Answer Acceptable Ans. Marks

3a (i) voltage = current resistance or current = voltage/resistance

or resistance = voltage/current

V = IR I=V/R

R=V/I Reject: V = C x R

1

3a (ii) 4.5 nwn

volts or V or J/C or JC-1

or A

1

1

3b decrease increase

If written Increase decrease means opposite then give 1 mark only. Same for following decrease decrease scores 1 increase increase

scores 1

1

1


23

Q4: (a) The diagram shows how a student connects several components in a circuit. The

student uses four identical 1.5 volt cells.

(i) Identify component Y.

............................................................................................................................... (1)

(ii) The reading on ammeter Z is 50 mA.

What is the reading in milliamps on each of the other two ammeters?

ammeter W = ......................... mA ammeter X = ......................... mA (1)

(iii) The student expected the lamp to be brighter and the reading on the voltmeter to

be 6.0 V.

The voltmeter is working correctly.

Give two reasons why the reading on the voltmeter is less than 6.0 V.

1 .............................................................................................................................

............................................................................................................................... (1)

2 .............................................................................................................................

............................................................................................................................... (1)

(b) The graph shows how the current in a filament lamp varies with the voltage across

it.


24

Explain why the graph is not a straight line.

......................................................................................................................................

......................................................................................................................................

......................................................................................................................................

......................................................................................................................................

...................................................................................................................................... (3)

(Total 7 marks)


25

Question No.


4a (i) (semiconductor)diode Reject if written: LED light emitting diode

1

4a (ii) 50 50 both required 1

4a (iii) one cell is connected the wrong way some of the voltage is cross/used up by

diode/component Y/ ammeter(s)/(connecting) wire /switch

two cells cancel one another/not all facing the same way Reject battery, if written reference to resistance of these components /cells / whole circuit Reject the following voltage used up by/voltage across

voltmeter/lamp voltmeter does not have infinite resistance ignore reference to current and energy

2

4b any three points current increases increases temperature increases resistance

line or slope becomes less steep

voltage increases increases heat /

molecular movement non-ohmic / I not proportional to V/

decrease rate of increase /current levels off

1

1

1


26

Q6:(a) When you rub a polythene rod with a woollen cloth the rod becomes negatively

charged.

(i) Complete the labels on the diagram.

(1)

(ii) Explain why the polythene rod then remains negatively charged for some time.

...............................................................................................................................

...............................................................................................................................

............................................................................................................................... (2)

(iii) If you rub a copper rod rather than a polythene rod, the copper rod will not stay

charged. Why not?

...............................................................................................................................

............................................................................................................................... (1)

(b) Complete the following.

When a petrol tanker is filled or emptied the build-up of charge can be dangerous.

This is because a ........................................ may occur and this can ignite the petrol

vapour and cause an explosion. (1)

(Total 5 marks)


27

Answer

Question No.


6a (i) electrons electrons both required 1

6a (ii) points in either order polythene is an (electrical) insulator

(so) slow to discharge /retains charge

poor / bad (electrical) conductor Reject: poor conductor of heat

charge (or electrons)leak away /move slowly (to earth)

1

1

6a (iii) copper is an (electrical) conductor (so charge is earthed)

Reject: copper is a good conductor of heat

1

6 b spark/sparking Reject: flame 1


28

Q16: (a) Complete the sentence:

Voltage is the .............................. transferred per unit .............................. passed. (1)

(b) The circuit diagram shows a 1.5 V cell connected to a resistor. The current in the

circuit is 0.60 A.

(i) How much charge in coulombs flows through the cell in 2.0 s?

...............................................................................................................................

Charge flowing = ................................................. C (2)

(ii) How much energy in joules is transferred to the resistor during this time?

...............................................................................................................................

Energy transferred = ............................................... J (2)

(iii) State one assumption you have made in (ii).

...............................................................................................................................

............................................................................................................................... (1)

(c) State two changes to the value of the circuit components that would each allow four

times as much energy to be transferred to a resistor in a two-second period.

1 ...................................................................................................................................

2 ................................................................................................................................... (2)

(Total 8 marks)


29

Answer

Question

No.

Correct Ans. Acceptable Ans. Reject Marks

16 a energy charge Joules coulomb 1

16b (i) Q = I t / 0.60 2 = 1.2 (C) nwn

1

1

16b (ii) 1.5 1.2 = 1.8 (J) nwn

Allow ecf 1

1

16b (iii) no heat/energy lost in wires or internal resistance or cell

cell has no internal resistance/ all cells voltage across resistor/wires have no resistance

no heat loss

100% efficient 1

16c double cell voltage quarter resistance value

3V add another cell 0.625 4 resistance wire area 2 x diameter or radius

resistance wire length

1

1


30

2008 Nov

Q1: The diagram shows an electric circuit.

(a) What do the symbols, A, B, C and D, represent?

A ............................................................................................................................... (1)

B ............................................................................................................................... (1)

C ............................................................................................................................... (1)

D ............................................................................................................................... (1)

(b) A student connects two meters to M as shown.

Complete the table to name each meter and what it measures.

(2)

(Total 6 marks)


31

Answer

Question

No.


1a (A) a.c. (power supply) (B) (open) switch / switch which is off (C) (electric) motor (D) variable resistance / rheostat

do not credit just power supply do not credit meter

Each point

carry 1

mark.

Total 4

marks

1b (i) voltmeter voltage/potential difference/p.d.

both parts required do not accept voltameter voltemeter voltagemeter etc

1

1b (ii) ammeter current/rate of flow of charge

both parts required do not accept ampmeter if the meters in both (i) and (ii) are correct award (1) mark

1


32

Q5: (a) Explain why it may be dangerous to switch on a light when your hands are wet.

......................................................................................................................................

......................................................................................................................................

...................................................................................................................................... (2)

(b) Many electrical appliances have a metal casing.

A live wire comes into contact with the metal casing.

Explain how an earth wire and a fuse prevent the user receiving an electric shock.

Earth wire .....................................................................................................................

......................................................................................................................................

Fuse ...............................................................................................................................

...................................................................................................................................... (2)

(c) The resistance of a persons body is 10 000 ohms. A current of 0.020 amps will give the person a serious electric shock.

Use the equation

voltage = current resistance to calculate the minimum voltage in volts which will cause this.

......................................................................................................................................

......................................................................................................................................

Minimum voltage = ............................... V (2)

(Total 6 marks)


33

Answer

Question

No.


5a water is a good conductor (so increases chance of) (electric) shock /current in the body/heart failure

2

5b (large) current/flow of charge in earth wire melts fuse (wire) (in plug) and cuts off the supply/electricity/current

both required for this mark

2

5c 200 (V) allow (1) mark for just (V = ) 0.02 10 000

2


34

Q8: (a) A student connects a 12 V battery to a resistor as shown.

(i) Draw an arrow in the resistor to show the direction of electron flow. (1)

(ii) Explain your answer.

...............................................................................................................................

............................................................................................................................... (2)

(b) The potential difference across the wire AB is 0.20 V when the current in the circuit

is 3.0 A.

The student leaves the circuit connected for 4 minutes.

(i) How much energy in joules is transferred from the battery to the wire AB in this

time?

...............................................................................................................................

...............................................................................................................................

Energy transferred = .............................. J (2)

(ii) Into what form is this energy transformed?

............................................................................................................................... (1)

(c) The 12 V battery is now replaced by a 6 V battery.

(i) How much energy in joules is transferred from the 6 V battery to the wire AB in

4 minutes?

...............................................................................................................................

...............................................................................................................................

Energy transferred = .............................. J (2)

(ii) Explain your answer.

............................................................................................................................... (1)

(Total 9 marks)


35

Answer

Question

No.


8a(ii) electrons have ve charge flow from ve and / or to + ve

2

8b(i) 0.20 x 3.0 x 240 = 144 (J)

0.2 x 3 x 4 = 2.4 scores (0/2)

2

8b(ii) thermal/heat 1 8c(i) 0.10 x 1.5 x 240

= 36 (J) / quartered ecf from (b)(i) e.g 0.6(J)

2

8c(ii) I halved (V halved)

1


36

2009 June

Q6: In electrostatic paint spraying, the surface being painted is given a negative charge. The

paint emerges from the paint sprayer carrying a positive charge.

(a) The diagram shows a metal frame being painted.

(i) Why is the paint attracted to the surface of the frame?

............................................................................................................................... (1)

(ii) After one coat of this paint the paint is no longer attracted to the frame. Explain

why this is.

............................................................................................................................... (1)

(b) A feature of electrostatic paint spraying is that the back of the metal frame is painted.

Explain why this happens.

......................................................................................................................................

...................................................................................................................................... (1)

(c) A disadvantage of electrostatic paint spraying is that many other things like walls get

painted as well. Suggest how this can be avoided.

......................................................................................................................................

...................................................................................................................................... (1)

(d) Name two other uses of electrostatic charges.

1 ....................................................................................................................................

2 .................................................................................................................................... (2)

(Total 6 marks)


37

Answer

Question

No.


6a (i) opposite/unlike charges (attract)

+ and (attract)

1

6a (ii) now positively charged/ like charges repel

ignore neutral

1

6b charges on metal can move all over/ whole frame is charged/

back is negative

1

6c give them a positive charge/ cover them up

1

6d photocopier/fingerprinting (inkjet) printer removing pollution from chimneys sticking balloons to walls/any classroom demonstration

safe use of sparks

Reject :

prevent explosions on aircraft 2


38

Q11: The circuit diagram shows a metal filament lamp connected in series to a battery, a closed

switch and a component X.

(a) What is component X?

...................................................................................................................................... (1)

(b) Adjusting component X alters the current in the lamp.

Complete the sentence.

Current is the ........................................... of flow of ............................................ (1)

(c) Complete the table for the equation in the box by writing the unit name in full.

Q = I x t

Abbreviation for Quantity Unit for Quantity

Q

I

t

(3)

(d) (i) Name the particles which flow in the wire from A to B.

............................................................................................................................... (1)

(ii) Explain why they flow in this direction.

...............................................................................................................................

............................................................................................................................... (1)

(Total 7 marks)


39

Answer

Question

No.


11a variable resistance variable resistor

rheostat

resistance resistor

thermistor

1

11b rate ..... charge or any named charged particle

1

11c coulomb(s) amp(ere)(s)

sec(ond)(s)

C A s

ignore quantity e.g charge

1

1

1

11d(i) electrons

1

11d(ii) negatively charged or attracted to positive or

repelled from negative


40

2009 Nov

Q1: A student uses a hair dryer. The hair dryers plug contains a fuse. The diagram shows the fuse.

(a) Explain how the fuse prevents too large a current in the hair dryer.

......................................................................................................................................

...................................................................................................................................... (2)

(b) The hair dryer is rated at 240 V, 1500W. Calculate the current rating in amps of the

hair dryer.

......................................................................................................................................

......................................................................................................................................

Current = ....................................A (3)

(c) The fuse in the hair dryer blows and the student has to replace it.

The following fuses are available:

1A 3 A 5 A 13 A

i)Which fuse should the student choose? Put a cross ( ) in the correct box.

Fuse

Rating

Put

cross

1 A

3A

5A

13A

(ii) Explain your choice.

...............................................................................................................................

............................................................................................................................... (1)


41

(d) A hair dryer heats up air.

Name one other example of electrical heating used in the home.

...................................................................................................................................... (1)

(Total 8 marks)


42

Answer

Question

No.

Acceptable Ans. Extra Information Marks

1(a) wire melts/blows breaks circuit/no current

1

1(b) Use of P = V I 1500 / 240 = 6.25 (A)

3

1c(i) 13A 1 1c(ii) all the others would blow dop 1 1(d) toaster / oven / kettle /bread

machine /soldering iron etc.

not microwave 1


43

Q13: A laptop computer has a rechargeable battery.

The battery takes 4 hours to charge fully when a voltage of 6 V is used with a current of

1.2 A.

(a) Use the equation

energy transferred = current voltage time

to calculate the energy transferred.

Show your working and give the unit.

......................................................................................................................................

......................................................................................................................................

......................................................................................................................................

Energy = .................................................. (3)

(b) Complete the sentences.

(i) Voltage is the energy transferred per unit ................................................ passed. (1)

(ii) A volt is a joule per ................................................ . (1)

(Total 5 marks)


44

Answer

Question

No.


13a 103 680 (2) J/joules (1)

credit 4 60 60 (s) or 14400 (s) with (1) note 28.8 J/joules is (2) and 28.8 is (1) and 1728 J/joules is (2)

3

13b(i) charge 1 13b(ii) coulomb allow minor misspellings

allow C 1


45

2010 June

Q1: The circuit diagram shows how a student connects several components.

These include four identical 1.5 volt cells.

(a) Identify component X.

...................................................................................................................................... (1)

(b) State a difference between a fixed resistor and a variable resistor.

......................................................................................................................................

...................................................................................................................................... (1)

(c) (i) Complete the sentence.

The four 1.5 volt cells are called a ........................................................................ (1)

(ii) Calculate the voltage, in volts, across the four cells.

...............................................................................................................................

Voltage = ............................. V (1)

(iii) The voltage across the fixed resistor is 3.8 V.

Calculate the voltage, in volts, across the rest of the circuit.

...............................................................................................................................

Voltage across the rest of the circuit = ................................. V (1)

(d) The reading on ammeter R is 40 mA.

State the reading in milliamps on each of the other two ammeters.

ammeter P = .................... mA ammeter Q = .................... mA (1)

(Total 6 marks)


46

Answer

Question

No.


1a (semiconductor) diode accept light emitting diode/LED (half-wave) rectifier

1

1b can change the resistance of a variable (resistor) variable (resistor) can change current/voltage

or the converse or the converse must refer to I, V or R ignore reference to symbo

1

1c(i) (6 volt) battery (of cells) dna power supply 1 1c(ii) 6 (V) 1 1c(iii) 2.2 (V) ecf candidates cii 3.8 1d 40 (mA).40 (mA). both required 1


47

Q7: A balloon is rubbed with a dry cloth on a dry day.

The balloon then sticks to a wall.

This is because the balloon has gained negative charge.

Complete the following sentences.

(a) As the balloon is rubbed, .............................................. are transferred

from the .............................................. to the ..............................................

by .............................................. . (3)

(b) The surface of the wall near to the balloon has a ..............................................charge.

This is because objects with .............................................. charges attract each other. (2)

(Total 5 marks)


48

Answer

Question

No.


7a (negative) electrons (dry) cloth .. balloon friction

dna negative charges both required correct order essential

1

1

1

7b positive /+ opposite/unlike

Accept different 1

1


49

Q9: (a) Put a cross ( ) in front of two statements to show which of the following statements are

correct.

A 1 V is the ratio of energy transferred to charge passed.

B 1 V is the voltage when a current of 1 A dissipates 1 W of power.

C 1 V is the voltage when 1 J of energy is transferred when 1 C of charge passes.

D 1 V is the ratio of resistance to current.

(2)

(b) The diagram shows a battery connected to a resistor.

The terms conventional flow and electron flow are both used in current electricity.

(i) Which one is represented by the arrow in this circuit?

.......................................... flow (1)

(ii) Explain your answer in (i).

...............................................................................................................................

............................................................................................................................... (1)

(iii) A student set up this circuit.

She added an ammeter to measure the current in the circuit and a voltmeter to

measure the voltage across the resistor.

Add these meters to the circuit diagram. (2)


50

(c) The student also had a stopwatch.

She recorded the following readings:

V = 3.0 V I = 0.75 A t = 2.0 minutes. Calculate:

(i) the charge, in coulombs, passing through the resistor in 2.0 minutes

...............................................................................................................................

...............................................................................................................................

Charge = .............................. C. (2)

(ii) the energy, in joules, transferred to the resistor in 2.0 minutes.

...............................................................................................................................

...............................................................................................................................

Energy transferred = ................................. J (2)

(Total 10 marks)


51

Answer

Question

No.


9a B (2nd definition) C (3rd definition)

if more than two crosses, -1 for each additional cross

1

1

9b(i) electron (flow) 1 9b(ii) electrons travel from /towards +

/electrons are negative(ly charged) dop

1

9b(iii) ammeter in series voltmeter in parallel with resistor or battery

allow extra ammeters if in series but not in middle of battery

1

1

9c(i) Q = I x t = 0.75 x 120 = 90 (C)

0.75 x 2 = 1.5 (C) scores 1st mark only

1

1

9c(ii) (E = IVt =) 0.75 x 3.0 x 120 = 270 (J) or

(E = QV =) 90 3 = 270 (J)

do not penalise use of t = 2 here if already penalised in c(i), in which case an answer of 4.5 (J) scores 2 ecf their value of Q from c(i) e.g. 1.5 x 3 = 4.5 (J) scores 2

1

1


52

2010 Nov

Q1: (a) State an equation which relates voltage, current and resistance.

...................................................................................................................................... (1)

(b) There is an electric current in a copper wire.

(i) Complete the sentence.

This electric current is the rate of flow of ............................................................. (1)

(ii) The copper wire is replaced by an aluminium wire.

This wire has the same thickness and the same length but a greater resistance.

What effect, if any, does this have on the electric current?

............................................................................................................................... (1)

(c) The following circuit diagram shows the places where a student measures the current

in a circuit.

(i) Identify component V.

............................................................................................................................... (1)

(ii) State the reading in amps on

ammeter Y reading = .........A

ammeter Z reading = .........A (2)


53

(d) The following circuit diagram shows how a toymaker connects the lights in a toy

house.

(i) Complete the sentence.

The lights in the toy house are connected in ......................................................... (1)

(ii) Suggest one advantage of connecting the lights in this way.

...............................................................................................................................

............................................................................................................................... (1)

(Total 8 marks)


54

Answer

Question

No.


1a voltage = current x resistance V = I x R

or any transposed version allow symbols

1

1b(i) charge/electrons /coulombs

dna ions

1

1b(ii) lower/less/smaller/weaker/not as strong

dna slower or slows down

1

1c(i) variable resistor/rheostat

dna just resistor

1

1c(ii) ammeter Y 0.8 (A) ammeter Z 1.2 (A)

1

1

1d(i) parallel

1

1d(ii) any one of lights can be switched on/off independently if a light fails the others will remain on lights may not fade as extra light switched on

dna same brightness

1


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Edexcel IGCSE Section 2 Electricity