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Name: No. IC:.

PENGGAL 2 960/2 STPM 2015

JABATAN PENDIDIKAN NEGERI KELANTAN

SIJIL TINGGI PERSEKOLAHAN MALAYSIA

PHYSICS 2 (FIZIK 2)

MODUL 1 One and a half hours ( Satu jam setengah)

Instructions to candidates:

DO NOT OPEN THIS QUESTIONS PAPER UNTIL YOU

ARE TOLD TO DO SO.

There are fifteen questions in Section A. For each questions, four

choices of answers are given. Choose one correct answer and

indicate it on the Multiple-choice Answer Sheet provided. Read the

instructions on the Multiple-choice Answer Sheet very carefully.

Answer all questions. Marks will not be deducted for wrong answers.

Answer all questions in Section B. Write your answers in the

spaces provided.

Answer any two questions in Section C. All essential working

should be shown. For numerical answers, unit should be quoted

wherever appropriate. Begin each answer on a fresh sheet of paper

and arrange your answers in numerical order.

Tear off the front page of this question paper in your answer

sheets of Section B, and tie both of them together with your answer

sheets in Section C.

Values of constant are provided.

Answers may be written in either English or Bahasa Malaysia

For examiners use (Untuk kegunaan

pemeriksa)

Section A

(Bahagian A)

Section B

(Bahagian B)

16

17

Section C

(Bahagian C)

Total

(Jumlah)

This question paper consists of 12 printed pages and 0 blank pages.

(Kertas soalan ini terdiri daripada 12 halaman bercetak dan 0 halaman kosong.)

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Answer all questions in this section

1. Which of the following physical quantities does not have a value of zero on the surface

of an isolated conductor?

A Electric potential at the surface

B Current flowing on the surface.

C Magnetic field near the surface.

D Electric field along the surface.

2 Three charges are located along the x axis as shown in the drawing. The mass of the

1.2 C is 4.0 109 kg. Determine the magnitude and direction of the acceleration of the

1.2 C charge when it is allowed to move if the other two charges remain fixed.

A 2 105 ms-2, to the right

B 1 105 ms-2, to the left

C 7 104 ms-2, to the right

D 3 105 ms-2, to the left

3 A capacitor of capacitance 15F is fully charged and the potential difference across its

plate is 8.0V. It is then connected into the circuit as shown

The switch S is closed at time t = 0. Which one of the following statements is correct?

Section A [15 marks]

3

A the time constant of the circuit is 6.0ms.

B The initial charge on the capacitor is 12C.

C After a time equal to twice the time constant, the charge remaining on the capacitor is

Qoe2, where Qo ts the charge at timen t=0.

D After a time equal to the time constant, the potential difference across the capacitor is

2.9V.

4. The circuit diagram shows two capacitors of capacitances 300 F and 500 F connected

in series with a 6.0 V battery.

The charge in the 300 F capacitor is

A 0.68 mC C 1.8 mC

B 1.1 mC D 4.8 mC

5 Which of the following circuits show a bridge circuit which is not in equilibrium?

4

6 In the circuit below, the ammeter reading is I and the voltmeter reading is V.

When of the switch is closed, which row describes what happens to I and V ?

I V

A decreases decreases to zero

B increases decreases to zero

C increases stays the same

D stays the same increases

7 The principles of conservation of which two quantities are associated with Kirchhoffs first

and second laws?

First Law Second Law

A charge energy

B charge voltage

C energy charge

D voltage charge

8 A conducting loop of wire is placed in a magnetic field that is normal to the plane of the

loop. Which one of the following actions will not result in an induced current in the loop?

A Rotate the loop about an axis that is parallel to the field and passes through the center of

the loop.

B Increase the strength of the magnetic field.

C Decrease the area of the loop.

D Decrease the strength of the magnetic field.

5

9 The current in a solenoid is decreased to one-half of its original value. Which one of the

following statements is true concerning the self-inductance of the solenoid?

A The self-inductance does not change.

B The self-inductance increases by a factor of two.

C The self-inductance decreases by a factor of two.

D The self-inductance increases by a factor of four.

10 Four long straight parallel wires carry equal currents directed vertically out of the page.

They are arranged on the corners of a square as shown in the figure below

The direction of the resultant magnetic force exerted on the wire labelled X is

A. south.

B. north.

C. west.

D. east.

11 In the above figure, a wire and a 10 ohm resistor are used to form a circuit in the shape

of a square, 20 cm by 20 cm. A uniform but non-steady magnetic field is directed into the

plane of the circuit. The magnitude of the magnetic field is decreased from 0.60 T to 0.20 T

in a time interval of 45 ms. The average induced current and its direction through the

resistor, in this time interval, are closest to:

6

A 36 mA, from b to a

B 21 mA, from b to a

C 36 mA, from a to b

D 21 mA, from a to b

12 An a.c. supply is connected to a resistor. When the peak value of the e.m.f. of the

supply is Vo and the frequency is f, the main power dissipated in the resistor in P. The

supply frequency is then changed to 2f, the peak value of the e.m.f. remaining as Vo.

What is now the mean power in the resistor?

A P

B

C 2P

D 4P

13 Two concentric rings X and Y are placed on the horizontal plane, as shown in the

diagram below.

The radius of ring X is r1= 1.0 m and r2 = 2.0 m. The current flows in ring Y is four times the

current in ring X but in the opposite direction. The resultant magnetic flux density at the

centre of the rings is

A Io5.1 and points towards N B Io5.0 and points towards N

C Io5.0 and points towards S D Io5.1 and points towards S

X

Y

N

r1 r2

I

4I

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14 The table below shows the values of the resistance, capacitive reactance and inductive

reactance for five RCL circuits. In which circuit will the voltage lead the current?

Resistance Capacitive reactance Inductive reactance

A 30 219 180

B 50 288 244

C 120 58 18

D 150 79 212

15 A variable capacitor is connected to an ac source. What effect does decreasing the

capacitance have on the reactance and current in this circuit?

Reactance Current

A decreases no change

B increases increases

C decreases increases

D increases decreases

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SECTION B [15 Marks]

Answer all questions in this section

16. Two metal spheres X and Y which are far apart are joined by a wire. The radius of

sphere X is 1r and that of sphere Y is 2r . The charge densities on the surface of the sphere

X and Y are 1 and 2 respectively.

(a) Find, in terms of 1 and 2

(i) the ratio of the electric field intensity on the surface of sphere to that on the

surface of sphere Y.

[3 Marks]

(ii) the ratio of the electric potential the surface of X to that of Y.

[1 Mark]

(b) Hence find the ratio of 2

1

, in terms of 1r and 2r .

[2 Mark]

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17 (a) Define self-inductance

. [2 marks]

(b) A constant e.m.f. of 1.04 V is induced by a changing current in a coil of inductance

0.26H. The initial current is 13.0 A. Calculate, after 2.0 s of supplying the current,

(i) the current in the coil,

[3 marks]

(ii) the magnetic flux linkage in the coil.

[2 marks]

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Section C [30 Marks]

Answer two questions only in this section

18. An alternating voltage is represented by V = 2.0 sin 314t

(a) What is

(i) the frequency [1 mark]

(ii) the r.m.s. voltage for this a.c.? [2 marks]

(b) The a.c. referred to in (a) is connected to a pure inductor of 5 mH.

(i) Explain why this inductor produces an e.m.f. which opposes the supply voltage.

[2 Marks]

(ii) At a particular instant the supply voltage is 1.0 V What is the back e.m.f. in the

inductor at that instant?

[1 Mark]

(iii) What is the r.m.s. current that flows in this inductor?

[2 Marks]

(c) (i) Sketch a graph to show the variation of voltage across the inductor with time. On

the same axes, sketch the graph of the variation of current in the inductor with time.

[3 Marks]

(ii) Based on the graph in (c)(i), explain why the average power supplied to the

inductor is zero.

[3 Marks]

19 (a) An electric iron is labelled 240 V; 1.2 kW What do you understand by the labelling?

[2 marks]

(b) (i) Define drift velocity. [2 marks]

(ii) Copper has a molar mass of 3105.63 kg and a density of 8900 kg 3m .

Assuming that each copper atom contribute one free electron, calculate the drift

velocity of the electrons in a copper wire of radius 1.0 mm carrying a current of

0.15A.

[6 marks]

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(c) A copper conducting rod carries a current of 15.0 A. The cross-sectional area of the

copper rod is a square of side 4.0 mm and its length is 60 m. Copper has a resistivity of

1.69x 10-8 m. Calculate

(i) the density of the current in the copper rod, [3 marks]

(ii) the resistance of the copper rod. [2 marks]

20. (a) Explain the meaning of the Hall effect. Describe a simple experiment to demonstrate

the Hall effect.

[5 Marks]

(b) The figure shows a conductor where the majority of the charge carriers are free electrons

of charge e and volume density n. The dimensions of the conductor are as shown. The

conductor carries a current I and is in a magnetic field of flux density B.

(i) Derive an expression for the Hall voltage produced in a conductor in terms of the

quantities mentioned above.

[4 Marks]

(ii) State the polarities of the Hall voltage.

[2 Marks]

(iii) What information may be deduced from the magnitude and direction of the Hall voltage

produced in a conductor?

[4 Marks]

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Values of constants

(Nilai Pemalar)

Acceleration of free fall

Avogadro constant

Boltzmann constant

Gravitational constant

Magnitude of electronic

charge

Mass of the Earth

Mass of the Sun

Molar gas constant

Permeability of free space

Permittivity of free space

Plancks constant

Radius of the Earth

Radius of the Sun Rest mass

of electron

Rest mass of proton

Speed of light in free space

Stefan-Boltzmann constant

Unified atomic mass unit

(Pecutan jatuh bebas)

(Pemalar Avogadro)

(Pemalar Boltzmann)

(Pemalar graviti)

(Magnitud cas elektron)

(Jisim Bumi)

(Jisim Matahari)

(Pemalar gas molar)

(Ketelapan ruang bebas)

(Ketelusan ruang bebas)

(Pemalar Planck)

(Jejari Bumi)

(Jejari Matahari)

(Jisim rehat elektron)

(Jisim rehat proton)

(Laju cahaya dalam ruang bebas)

(Pemalar Stefan-Boltzmann)

(Unit jisim atom bersatu)

g = 9.81 m s-2

NA = 6.02 x 1023

mol-1

k, kB = 1.38 x 10-23

J K-1

G = 6.67 x 10-11

N m2 kg

-2

e = 1.60 x 10-19

C

ME = 5.97 x 1024

kg

MS = 1.99 x 1030

kg

R = 8.31 J K-1

mol-1

0 = 4 x 10-7

H m-1

0 = 8.85 x 10-12

F m-1

= (

)

h = 6.63 x 10-34

J s

RE = 6.38 x 106 m

RS = 6.96 x 108 m

me = 9.11 x 10-31

kg

mp = 1.67 x 10-27

kg

c = 3.00 x 108 m s

-1

= 5.67 x 10-8 W m-2 K-4

u = 1.66 x 10-27

kg