TRIAL SEM 2 SMK TAMAN FOREST HEIGHTS 2022

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SEKOLAH MENENGAH KEBANGSAAN TAMAN FOREST HEIGHTS

1 Hour 30 Minutes

Instructions to candidates:
DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE TOLD TO DO SO.

Answer all questions in Section A.
Answer all questions in Section B.
Answer two questions only in Section C.
All working should be shown. For numerical answers, units should be quoted wherever
appropriate.
Answers may be written in English or Malay.
Fill in your personal details on page 7.

Prepared by, Checked by, Verified by,

(KANG SEOW HUNG) (NORAZIZAH BINTI MAAROF) (CHAN SOOK LAI)
Subject Teacher Head of Physics’ Panel Head of Science and Mathematics
Department
SMK Taman Forest Heights

___________________________________________________________________________

This question paper consists of 12 printed pages and 2 blank pages.

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Section A [15 marks]
Answer all questions in this section.

1. Two-point charges of − 1.5 and + 6.4 are separated by a distance of 0.50 m. What
is the force that experienced by both charges?

A 0.35 N B 0.56 N C 1.2 N D 1.9 N

2. Three electrons are situated at the vertices of an equilateral triangle of side a. What is the
potential energy of the system?

A 2 2 B 3 2 C 12 2 D 3 2
4 4 2 4

3. A dielectric material is inserted into the space between the parallel plates of a capacitor
originally filled with air. Which of the following correctly summarizes the change, if any, in
the potential difference and capacitance of the capacitor?

Potential difference Capacitance

A Decreases Increases
B Increases Increases
C Increases Decreases
D Decreases Decreases

4. Two charged capacitors each with capacitance C, and two resistors each with resistance R,
are connected in a circuit as shown in the figure below.

CC

Switch

R

R

What is the time constant of the circuit in the figure when the switch is closed?

A 1 B 1 C D 2

4 2

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5. When the potential difference across a copper wire decreases, which one of the following

describing about the drift velocity, v and the number of free electrons per unit volume, n is

true?

vn

A No change No change

B No Change Decreases

C Increases Decreases

D Decreases No change

6. A particular wire has cross-sectional area 0.5 mm2 and resistivity 2.5 x 10-7  m. What is
the length of the wire needed to make a heater rated at 72 W to operate from a constant 12 V
supply?

A 4.0 B 40 C 4.0 D 40

7. Which one of the following is the best statement describes the phenomenon of
superconductivity?

A The resistance of the material will increase at very low temperature.
B The resistance of the material will become constant at very low temperature.
C The resistance of the material is independent to the change of temperature
D The resistance of the material will become almost zero at very low temperature.

8. A galvanometer has an internal resistance of 40  and it gives a full-scale deflection of
20 mA. If it is to be converted into a voltmeter capable of measuring a maximum voltage of
6.0 V. What is the resistance of the multiplier to be connected in series?

A 260  B 270  C 300  D 320 

9. In the circuit shown below, the two batteries have negligible internal resistance .

Determine the e.m.f. E.

A 6.70 B 8.60 C 12.2 D 25.6

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10. A circuit which is used to compare the resistance R of an unknown resistor with a 100 Ω
standard resistor is shown below. The distances L from one end of the potentiometer slide wire
to the balanced point J are 58.0 cm and 75.0 cm when X is connected to Y and to Z respectively.
The length of the slide-wire is 100.0 cm.

A LJ B
GX

100 Ω Y R Z



Calculate the value of the resistance R.

A 22.7 B 29.3 C 62.7 D 93.2

11. Battery of e.m.f. 1.5 V and 9.0 V are connected in series with two resistors of resistances
2.0 Ω and 1.0 Ω as shown below.

2.0 Ω

A 1.0 Ω 9.0 V B
1.5 V D 5.0 V

Determine the potential difference between AB.

A 0.50 V B 1.5 V C 3.5 V

12. An electron travelling with a velocity 1.5 106 −1 enters a velocity selector with
combined electric field of 6.75x104 V m−1 and magnetic field of 45 mT.

+

xx

xx

-

What is the acceleration of the electron when the electric field is switched off?
A 1.21x1015 m s−2 B 1.21x1016 m s−2 C 1.19x1016 m s−2 D 2.19x1019 m s−2

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13. A rigid wire with resistance 5.0 Ω m-1 slides with a constant speed of 20 cm s-1 along a U-
shaped metal track of negligible resistance shown below.

In a uniform magnetic field of 1.5 T acts perpendicularly to the plane of the track, determine
the current induced in the wire.

A 0.010 B 0.020 C 0.040 D 0.060

14. A battery of e.m.f. 12 V connected in series with a 10.0 Ω resistor and a 6.0 H inductor.

What is rate of change of current at the instant the switch is closed?

A 1.2 −1 B 2.0 −1 C 2.4 −1 D 3.0 −1

15. An alternating current produces three times the amount of heat as that produced by 4.0 A
direct current when both type of currents flow through the same resistor. Determine the peak
value of the alternating current.

A 4.90 A B 5.66 A C 9.80 A D 15.0 A

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Name: ………………………………………………………….. Class: ……………………

Identity card number:…………………...… Centre number/index number:…………………...

(Nombor kad pengenalan) (Nombor pusat/angka giliran)

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SIJIL TINGGI PERSEKOLAHAN MALAYSIA
(MALAYSIA HIGHER SCHOOL CERTIFICATE)

Instructions to candidates:

Tear off pages 7, 8 and 9 of your answer sheets of Section B, and tie them together with your
answer sheets of Section C.

For examiner’s use
(Untuk kegunaan

pemeriksa)

Section B
(Bahagian B)
16

17

Section C
(Bahagian C)

Total
(Jumlah)

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Section B [15 marks]
Answer all questions.
Write the answers in the spaces provided.

16. A parallel plate capacitor consists of two metal plates, each of area 1.00 cm2 and separated
by a distance of 4.0 mm in air. The capacitor is charged to a potential difference of 120 V.

(a) Calculate the capacitance of the capacitor. [2 marks]

(b) Calculate the energy stored in the capacitor. [2 marks]

(c) The charged parallel-plate capacitor is then disconnected from the supply. The space
between the plates is then filled with an insulator.

(i) Explain in molecular terms, the change in the electric field between the plates. [2 marks]

(ii) Hence deduce the change in the capacitance of the capacitor. [2 marks]

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17. A 20 μF capacitor is connected across a power source which produces an alternating voltage
V given by = 283 sin 500 where V in volts and t in seconds.

(a) Determine the frequency of the alternating voltage. [1 mark]

(b) Determine the reactance of the capacitor. [1 mark]

(c) Determine the maximum power supplied to the capacitor. [3 marks]

(d) On the same axes, draw the graphs to show the variation of the power P and voltage V with

time t across the capacitor. [2 marks]

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Section C [30 marks]
Answer two questions only.

You may answer all the questions, but only the first two answers will be marked.
Write the answers on the answer sheets provided. Begin each answer on a new page of the
answer sheet.

18. (a) Define electric field strength and electric potential at a point in an electric field.

[2 marks]

(b) Draw a diagram to show the charge distribution and the electric field lines produced by a

negative charged conducting sphere. [2 marks]

(c) Define Gauss’s law. [1 mark]

(d) A positive point charge q = 5.0 µC is surrounded by a sphere with radius 20.0 cm centered
on the charge.

q = 5.0 µC

+

Determine the electric field strength E at any point on the surface of the sphere due to this
charge, and hence determine the electric flux which passes through the sphere. [5 marks]

(e) Two parallel charged conducting plates kept at 1.20 mm apart are charged with opposite
charges of the same magnitude with a potential difference of 200 V as shown below.

E
+-
+-

+-

+-

+-

+-

(i) Derive an expression for the electric field strength E at any point between the two parallel

charged conducting plates in terms of charge density and . [3 marks]

(ii) Calculate the charge density on any one plate. [2 marks]

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19. (a) Define electromotive force (e.m.f.), of an electric source. [1 mark]

(b) Explain the mechanism of electrical conduction in a conductor when it is connected to a

battery. [3 marks]

(c) An electric heater is labelled 240 V; 1.5 kW. What do you understand by the labelling?
[2 marks]

(d) A cable used in high-voltage power transmission consists of six copper wires surrounding
an aluminium wire. A cross-section is shown in the diagram below.

copper

aluminium

The resistance of a length of 1.0 km of the aluminium wire is 0.53 Ω. The resistance of a length
of 1.0 km of one of the copper wires is 0.33 Ω. Each wire has a diameter of 8.2 mm.

(i) Calculate the resistivity of aluminium. [3 marks]

(ii) Explain why only a small percentage of the total current in the cable passes through the

aluminium wire. [2 marks]

(iii) The potential difference across a length of 1.0 km of the cable is 80 V. Calculate the total

power loss for a 1.0 km length of cable. [3 marks]

(iv) State one way to reduce the power loss in the cable. [1 mark]

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20. (a) Define magnetic flux density. [1 mark]

(b) A wire of length 4.0 cm carrying a current of 8.0 A is placed perpendicularly to a magnetic
field of 0.30 T as shown below.



Determine the magnitude and direction of the magnetic force acting on the wire. [3 marks]

(c) The wire of length 4.0 cm carrying a current of 8.0 A and has a weight of 8.0 g is hanged
on two thin conductors. It is deflected from the vertical through an angle of 15° in a uniform
magnetic field as shown below.

Determine the magnetic flux density of the magnetic field. [4 marks]

(d) Describe Hall effect. [2 marks]

(e) A copper slab of dimension 10.0 cm x 1.0 cm x 1.0 cm carrying a current I of 20.0 A in a
uniform magnetic field B of 8.0 T acting perpendicularly on the conductor as shown below.



1.0 cm

10.0 cm 1.0 cm

Given the density of free electrons in copper is 8.50 x 1028 m-3. [1 mark]
[2 marks]
(i) Determine the electric pole on the shaded area. [2 marks]
(ii) Determine the drift velocity of the free electrons.
(iii) Determine the Hall Voltage established across the copper slab.

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Values of constants

Acceleration of free fall g = 9.81 m s−2

Avogadro’s constant NA = 6.02 × 1023 mol−1
Boltzmann’s constant k, kB = 1.38 × 10−23 J K−1
Gravitational constant G = 6.67 × 10−11 N m2 kg−2

Magnitude of electronic charge e = 1.60 × 10−19 C

Mass of the Earth ME = 5.97 × 1024 kg

Mass of the Sun MS = 1.99 × 1030 kg
Molar gas constant R = 8.31 J K−1 mol−1

Permeability of free space μ0 = 4π × 10−7 H m−1
Permittivity of free space ε0 = 8.85 × 10−12 F m−1

= (1) 10−9 F m-1

36

Planck’s constant h = 6.63 × 10−34 J s

Radius of the Earth RE = 6.38 × 106 m

Radius of the Sun RS = 6.96 × 108 m
Rest mass of electron me = 9.11 × 10−31 kg
Rest mass of proton mp = 1.67 × 10−27 kg
Speed of light in free space c = 3.00 × 108 m s−1

Stefan-Boltzmann constant σ = 5.67 × 10−8 W m−2 K−4

Unified atomic mass unit u = 1.66 × 10−27 kg

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1A Marking Scheme
2D
3A Physics Paper 2
4A Trial Exam STPM 2022
5D
Prepared by Pn. Kang Seow Hung

Section A [15 marks] 11 D
6C 12 C
7D 13 D
8A 14 B
9D 15 C
10 B

1. Two-point charges of − 1.5 and + 6.4 are separated by a distance of 0.50 m. What
is the force that experienced by both charges?

A 0.35 N B 0.56 N C 1.2 N D 1.9 N

Ans: A


= 4 2

1.5 10−6(6.4 10−6)
= 4 (8.85 10−12)(0.50)2
= 0.35

2. Three electrons are situated at the vertices of an equilateral triangle of side a. What is the
potential energy of the system?

A 2 2 B 3 2 C 12 2 D 3 2
4 2
4 4

Ans: D


= 4
2 2 2

= 4 + 4 + 4
3 2

= 4

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3. A dielectric material is inserted into the space between the parallel plates of a capacitor
originally filled with air. Which of the following correctly summarizes the change, if any, in
the potential difference and capacitance of the capacitor?

Potential difference Capacitance

A Decreases Increases
B Increases Increases
C Increases Decreases
D Decreases Decreases

Ans: A

4. Two charged capacitors each with capacitance C, and two resistors each with resistance R,
are connected in a circuit as shown in the figure below.

CC

Switch

R

R

What is the time constant of the circuit in the figure when the switch is closed?

A 1 B 1 C D 2

4 2

Ans: A

1 =1+1 → =
2

1 =1+1
→ = 2

1
= = 2 (2) = 4

5. When the potential difference across a copper wire decreases, which one of the following

describing about the drift velocity, v and the number of free electrons per unit volume, n is

true?

vn

A No change No change

B No Change Decreases

C Increases Decreases

D Decreases No change

Ans: D V=IR and I=Anev, n is constant

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6. A particular wire has cross-sectional area 0.5 mm2 and resistivity 2.5 x 10-7  m. What is
the length of the wire needed to make a heater rated at 72 W to operate from a constant 12 V
supply?

A 4.0 B 40 C 4.0 D 40

Ans: C
2 =

= (2.5 10−7)
122 2.0 = 0.5 10−6
= 4.0
72 =
= 2.0

7. Which one of the following is the best statement describes the phenomenon of
superconductivity?

A The resistance of the material will increase at very low temperature.
B The resistance of the material will become constant at very low temperature.
C The resistance of the material is independent to the change of temperature
D The resistance of the material will become almost zero at very low temperature.

Ans: D

8. A galvanometer has an internal resistance of 40  and it gives a full-scale deflection of
20 mA. If it is to be converted into a voltmeter capable of measuring a maximum voltage of
6.0 V. What is the resistance of the multiplier to be connected in series?

A 260  B 270  C 300  D 320 

Ans: A

6.0 = 20x10-3(40) + 20x10-3(RM)
RM = 260 

9. In the circuit shown below, the two batteries have negligible internal resistance .

Determine the e.m.f. E.

A 6.70 B 8.60 C 12.2 D 25.6

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Ans: D
I = 0.96 + 0.40=1.36 A

Upper loop Anticlockwise, [1]
7.2 – E +1.36(10.0) +0.96(5.0)= 0
7.2 – E = –1.36(10.0) –0.96(5.0)

E = 25.6 V [1]

10. A circuit which is used to compare the resistance R of an unknown resistor with a 100 Ω
standard resistor is shown below. The distances L from one end of the potentiometer slide wire
to the balanced point J are 58.0 cm and 75.0 cm when X is connected to Y and to Z respectively.
The length of the slide-wire is 100.0 cm.

L J B
A
G X
100 Ω Y R
Calculate the value of the resistance R. Z


A 22.7 B 29.3 C 62.7 D 93.2

Ans: B 100+ = 75.0
Use ,
100 58.0

75.0
∴ = (58.0 ) 100 − 100

= 29.3

11. Battery of e.m.f. 1.5 V and 9.0 V are connected in series with two resistors of resistances
2.0 Ω and 1.0 Ω as shown below.

Determine the potential difference between AB.

A 0.50 V B 1.5 V C 3.5 V D 5.0 V

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Ans: D

9.0 - 1.5 - (1.0+2.0) I = 0
I = 2.5 A
P.d. between AB = P.d. across 2.0 Ω resistor

= 2.5 x 2.0
= 5.0 V

12. An electron travelling with a velocity 1.5 106 −1 enters a velocity selector with
combined electric field of 6.75x104 V m−1 and magnetic field of 45 mT.

+
xx

xx

-

What is the acceleration of the electron when the electric field is switched off?

A 1.21x1015 m s−2 B 1.21x1016 m s−2 C 1.19x1016 m s−2 D 2.19x1019 m s−2

Ans: C
ma = evB

1.60x10−19(1.5x106)(0.045)
a = 9.11x10−31
a = 1.19x1016 m s−2

13. A rigid wire with resistance 5.0 Ω m-1 slides with a constant speed of 20 cm s-1 along a U-
shaped metal track of negligible resistance shown below.

In a uniform magnetic field of 1.5 T acts perpendicularly to the plane of the track, determine
the current induced in the wire.

A 0.010 B 0.020 C 0.040 D 0.060

Ans: D [Next page
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=
=

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=


=


= (1.5)(20 10−2)

5.0

= 0.060 60

14. A battery of e.m.f. 12 V connected in series with a 10.0 Ω resistor and a 6.0 H inductor.

What is rate of change of current at the instant the switch is closed?

A 1.2 −1 B 2.0 −1 C 2.4 −1 D 3.0 −1

Ans: B


= −
−12 = −6.0


= 2.0 −1 [1]

15. An alternating current produces three times the amount of heat as that produced by 4.0 A
direct current when both type of currents flow through the same resistor. Determine the peak
value of the alternating current?

A 4.90 A B 5.66 A C 9.80 A D 15.0 A
Ans: C
3(I2R)=1/2(Io2R)
3(4.02R)=1/2(Io2R)
Io = 9.80 A

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Section B [15 marks]
Answer all questions.
Write the answers in the spaces provided.

16. A parallel plate capacitor consists of two metal plates, each of area 1.00 cm2 and separated
by a distance of 4.0 mm in air. The capacitor is charged to a potential difference of 120 V.

(a) Calculate the capacitance of the capacitor. [2 marks]

= [1]
[1]

8.85 10−12(1.00 10−4)
= 4.0 10−3

= 2.21 10−13

(b) Calculate the energy stored in the capacitor. [2 marks]

= 1 2 [1]
2

= 1 (2.21 10−13)(120)2
2

= 1.59 10−9 [1]

(c) The charged parallel-plate capacitor is then disconnected from the supply. The space
between the plates is then filled with an insulator.

(i) Explain in molecular terms, the change in the electric field between the plates. [2 marks]

Molecules of the dielectric are polarised by electric field between the plates.
A reverse electric field strength, ER is set up in the dielectric. [1]
The resultant electric field is weaker than the initial electric field. [1]

(ii) Hence deduce the change in the capacitance of the capacitor. [2 marks]

From = , when electric field strength, E decreases, potential difference V between the


plates is reduced. [1]

From = , when V decreases, the capacitance C increases, the charge, Q remains constant.



[1]

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17. A 20 μF capacitor is connected across a power source which produces an alternating voltage
V given by = 283 sin 500 where V in volts and t in seconds.

(a) Determine the frequency of the alternating voltage. [1 mark]

= 500

2 = 500

= 250 Hz [1]

(b) Determine the reactance of the capacitor. [1 mark]

= 1
2

1
= 2 (250)(20 10−6)

= 31.8 [1]

(c) Determine the maximum power supplied to the capacitor. [3 marks]

= [1]

[1]
31.8 = 283 [1]


283
= 31.8

= 1
2

1 283
= 2 (31.8) 283

= 1.26 103

(d) On the same axes, draw the graphs to show the variation of the power P and voltage V with

time t across the capacitor. [2 marks]

V, P [2]

T

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Section C [30 marks]

18. (a) Define electric field strength and electric potential at a point in an electric field.
[2 marks]

Electric field strength, E at the point in an electric field is the electrostatic force per unit
positive charge.

The electric potential at one point in an electric field is the work done to bring a unit positive
charge from infinity to that point against electrostatic force.

(b) Draw a diagram to show the charge distribution and the electric field lines produced by a

negative charged conducting sphere. [2 marks]

- Q ሬ Ԧ

−− − −
−−
−

−

− −
−
− −−
−
−

(c) Define Gauss’s law. [1 mark]
[1]
The electric flux through a closed surface is given by equation

∅ = ∑ where ∑ = total charge enclosed by the surface



= permittivity of the free space

(d) A positive point charge q = 5.0 µC is surrounded by a sphere with radius 20.0 cm centered
on the charge.

q = 5.0 µC

+

Determine the electric field strength E at any point on the surface of the sphere due to this
charge, and hence determine the electric flux which passes through the sphere. [5 marks]

= [1]
4 2
5.0 10−6
= 4 (8.85 10−12)(0.20)2

= 1.12 106 −1 −1 [1]

Ф = [1] Or Ф = ∑ [1]

[1]
5.0 10−6 [1]
Ф = (1.12 106)4 (0.20)2 [1] Ф = 8.85 10−12

Ф = 5.63 105 Vm [1] Ф = 5.65 105 Vm

Note:

SI unit of electric flux, is V m (volt meters), or equivalent to N m2 C−1 (Newton meters squared per coulomb).

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CONFIDENTIAL* 10

(e) Two parallel charged conducting plates kept at 1.20 mm apart are charged with opposite
charges of the same magnitude with a potential difference of 200 V as shown below.

E
+-
+-

+-

+-

+-

+-

(i) Derive an expression for the electric field strength E at any point between the two parallel

charged conducting plates in terms of charge density and . [3 marks]

Electric flux through the Gaussian surface, = EA

If is the charge density on the plate, = ∑ ∴ ∑ = [1]

Using Gauss’s Law, = ∑

EEA==
[1]
[1]

(ii) Calculate the charge density on any one plate. [2 marks]


=

= [1]

=

200(8.85 10−12)
= 1.20 10−3
= 1.48 10−6 −2 or 1.475 10−6 −2[1]

19. (a) Define electromotive force (e.m.f.), of an electric source. [1 mark]
The e.m.f. of an electric source is the electrical energy supplied per unit charge flowing through
it. / that is imparted by an energy source

(b) Explain the mechanism of electrical conduction in a conductor when it is connected to a

battery. [3 marks]

When a conductor is connected to a battery, an electric field is set up in the conductor. [1]

The free electrons experience a net force in the direction opposite to the electric field and drift

in that direction. [1]

Charge is transferred and a current flow in the direction of the electric field. [1]

(c) An electric heater is labelled 240 V; 1.5 kW. What do you understand by the labelling? [2]

The normal operating voltage is 240 V. [1]
When a voltage of 240 V is supplied, the power dissipated by the electric heater is 1.5 kW. [1]

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CONFIDENTIAL* 11

(d) A cable used in high-voltage power transmission consists of six copper wires surrounding
an aluminium wire. A cross-section is shown in the diagram below.

copper

aluminium

The resistance of a length of 1.0 km of the aluminium wire is 0.53 Ω. The resistance of a length
of 1.0 km of one of the copper wires is 0.33 Ω. Each wire has a diameter of 8.2 mm.

(i) Calculate the resistivity of aluminium. [3 marks]

[1]
=
(1.0 103)
0.53 = (4.1 10−3)2 [1]

= 2.8 10−8 or 2.80 10−8 [1]

(ii) Explain why only a small percentage of the total current in the cable passes through the

aluminium wire. [2 marks]

11 [1]
= 6 ( . )
= .

≪

Resistance of aluminium wire (0.53 Ω) is much higher than the effective resistance of the six
copper wires (0.055 Ω). [1]

Therefore, the current flowing through the aluminium wire is very small compared to the

current through the copper wires.

(iii) The potential difference across a length of 1.0 km of the cable is 80 V. Calculate the total

power loss for a 1.0 km length of cable. [3 marks]

Total resistance, R: [1]

1 11
= 6 ( . ) + .
= .

Power loss for 1 km of cable:

= 2 [1]

802
= .
= . .
[1]

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CONFIDENTIAL* 12

(iv) State one way to reduce the power loss in the cable. [1 mark]
Use high transmission voltage so that the current is small. (From P=VI) [1]

20. (a) Define magnetic flux density. [1 mark]

Magnetic Force on a Moving Charge, Ԧ = ( Ԧ ሬԦ )

=

= where F=magnetic force



q = charge

v = velocity

θ = angle between Ԧ and ሬԦ [1]

(b) A wire of length 4.0 cm carrying a current of 8.0 A is placed perpendicularly to a magnetic
field of 0.30 T as shown below.



Determine the magnitude and direction of the magnetic force acting on the wire. [3 marks]

= [1]
= 0.30(8.0)(0.040)
= 0.096 [1] Acting upwards [1]

(c) The wire of length 4.0 cm carrying a current of 8.0 A and has a weight of 8.0 g is hanged
on two thin conductors. It is deflected from the vertical through an angle of 15° in a uniform
magnetic field as shown below.

Determine the magnetic flux density of the magnetic field. [4 marks]

2 = [1] [Next page
[1] CONFIDENTIAL*
2 =
[1]

∴ =

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CONFIDENTIAL* 13

15 = (8.0)(0.040)
0.0080(9.81)

= 0.0657 [1]

= .

(d) Describe Hall effect. [2 marks]

When a current carrying conducting slab is placed in a magnetic field, moving charge carriers
will experience force due to the magnetic field B. [1]
A small transverse/perpendicular potential difference is established. [1]

(e) A copper slab of dimension 10.0 cm x 1.0 cm x 1.0 cm carrying a current I of 20.0 A in a
uniform magnetic field B of 8.0 T acting perpendicularly on the conductor as shown below.



---------------------------------- 1.0 cm
+ + + -+-+- +- -+-+- -+-+- +- -+-+- -+-+- +- -+-+- -+-+- -+-+- +- -+-+-+- +- -+
+ + + -+-+- +- -+-+- -+-+- +- -+-+- -+-+- +- -+-+- -+-+- +- -+-+- -+-+-+- +- -+
+ + + + + + + + + + + + + + + + + + + + + + + + ++ + +
1.0 cm
10.0 cm

Given the density of free electrons in copper is 8.50 x 1028 m-3. [1 mark]
(i) Determine the electric pole on the shaded area. [2 marks]

Positive [1] [2 marks]

(ii) Determine the drift velocity of the free electrons. [1]
[1]
=
20.0 = (0.010 0.010) (8.50 1028)(1.60 10−19)

= 1.47 10−5 −1

(iii) Determine the Hall Voltage established across the copper slab.

= [1]
= 8.0(1.47 10−5)(0.010 ) [1]
= 1.2 x 10−6 1.18 x 10−6 1.18 [1]

or [1]


=

8.0(20.0)
= (8.50 1028)(1.60 10−19)(0.010 )
= 1.2 x 10−6 1.18 x 10−6 1.18

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