Download Secondary: 5E Date: 20/06/2011

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CCC Hoh Fuk Tong College
Second Term Examination 2010-2011
Physics
Secondary: 5E
Time allowed: 2
Date: 20/06/2011
1
hour (8:15a.m. – 10:45a.m.)
2
Max.: 120
GENERAL INSTRUCTIONS
1.
2.
There are TWO sections, A and B, in this Paper. Section A consists of
multiple-choice questions in this question book, while Section B contains
conventional questions printed separately in Question-Answer Book B. You
are advised to finish Section A in about 60 minutes.
Answers to Section A should be marked on the Multiple-choice Answer Sheet
while answers to Section B should be written in the spaces provided in
Question-Answer Book B.
The Answer Sheet for Section A and the Question-Answer Book for
Section B must be handed in separately at the end of the examination.
page 2 of 16
page 3 of 16
Section A – Multiple Choices (36 marks)
1.
Mary uses a piece of silk to rub a comb. The comb then becomes positively
charged. This net positive charge accumulates because the comb
A.
gains electrons.
B.
gains protons.
C.
loses electrons.
D.
loses protons.
2.
Two conducting spheres are hanging freely in air by insulating threads.
which of the following will the two spheres attract each other?
Note: ‘N’ denotes that the sphere is uncharged.
A.
B.
C.
D.
3.*
(1) only
(2) only
(3) only
(1), (2) and (3) only
Two charged spheres A and B are
hanging at a point on a ceiling by two
identical nylon threads. They remain at
rest as shown.
Which of the
following statements must be correct?
(1)
Both spheres carry positive charges.
(2)
(3)
A.
B.
C.
D.
The force acting on B by A is larger than the force acting on A by B.
The mass of A is larger than B.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
In
page 4 of 16
4.*
Two point charges with quantities of charges +Q and –Q are placed as shown
below.
+Q
-Q
If the size of the combined electric field strength at X is a, what is the size of
the electric field strength at Y?
5.
A.
4
a
9
B.
5
a
9
C.
8
a
9
D.
10
a
9
The following diagram shows three positive charges P, Q and R, which are
placed between two charged metal plates.
Which of the following statements about the force exerted on P, Q and R by
the electric field between the plates is correct?
A.
P experiences the weakest force while R experiences the strongest.
B.
P and R experience the weakest force while Q experiences the
strongest.
C.
P and R experience the strongest force while Q experiences the
weakest.
D.
The forces experienced by the three charges are the same.
page 5 of 16
6.*
The figure shows the location of an isolated charge of size +Q. The size (in
an arbitrary unit) of the electric field strength is marked at certain points.
What is the size (in the same arbitrary unit) of the electric field strength at X
and Y?
A.
B.
C.
D.
7.
electric field strength at X
72
electric field strength at Y
30
72
90
90
36
30
36
In the circuit shown below, a voltage of 10 V is applied across XY.
What is the current passing through the 8Ω resistor?
A.
0.5 A
B.
0.8 A
C.
1A
D.
2A
8.
In the above circuit, the bulbs are identical. The reading of ammeter A1 is 1
A. Find the readings of ammeters A2 and A3.
page 6 of 16
A.
B.
C.
D.
9.
Reading of A2
2A
2A
0.5 A
0.5 A
Reading of A3
2A
3A
1A
1.5 A
An ammeter and a 0 – 40 Ω rheostat are connected to a 6 V battery.
The
1
sliding contact is located at a position X where AX = 4 AB as shown.
Find the ammeter reading.
A.
0.15 A
B.
C.
D.
10.
0.2 A
0.45 A
0.6 A
In an experiment, Mary connects two identical conducting wires but of
different lengths in series. Which of the following statements is correct?
(1)
The current flowing through the two ends of the two wires is the same.
(2)
The voltage across the two ends of the two wires is the same.
(3)
The resistance of the longer wire is larger.
A.
B.
C.
D.
(1) only
(2) only
(1) and (2) only
(1) and (3) only
page 7 of 16
11.
The circuit is connected to a constant voltage
supply. The ammeter has negligible internal
resistance and registers a current of 1 A when
K is open.
What will be the ammeter reading when K is
closed？
A
B
C
D
12.
0.2 A
1A
4A
5A
Ammeters A1 and A2 are used to measure
the current flowing through the circuit.
What will happen to the ammeter readings
when switch S is closed?
A.
B.
C.
D.
13.
A1
increases
increases
increases
remains unchanged
A2
increases
decreases
remains unchanged
decreases
Two light bulbs are connected in parallel to a 12-V battery as shown below.
If the reading of the ammeter is 5 A and the power dissipated by bulb X is 24
W, find the power dissipated by bulb Y.
A.
12 W
B.
24 W
C.
36 W
D.
60 W
page 8 of 16
14.
If a 15 A fuse is installed in the plug of an electric kettle of rating ‘220 V , 900
W’, state what happens when the kettle is plugged in and switched on.
A.
The kettle will not operate.
B.
The kettle will be short-circuited.
C.
The output power of the kettle will be increased.
D.
The chance of the kettle being damaged by an excessive current will be
increased.
15.
The mains circuit supplies electricity at 220 V and is fitted with a fuse of 15 A.
Which of the following conditions may blow the fuse?
(1)
Three heaters rated at ‘220 V , 1200 W’ are connected in parallel to the
(2)
(3)
A.
B.
C.
D.
16.
mains.
Three heaters rated at ‘220 V , 1200 W’ are connected in series to the
mains.
Two heaters rated at ‘220 V , 1200 W’ are connected in parallel to the
mains and the live wire of one of them is accidentally earthed.
(2) only
(3) only
(1) and (3) only
(2) and (3) only
The following table shows three electrical appliances which John used last
month:
Electrical appliance
Rating
Duration
CD player
220 V , 98 W
50 hours
rice cooker
220 V , 800 W
21 hours
air-conditioner
220 V , 1300 W
270 hours
If 1 kWh of electricity costs $0.9, what is the cost of electricity used?
A.
$ 67.52
B.
C.
D.
$ 75.08
$ 335.43
$ 372.70
page 9 of 16
17.
Which of the following diagrams shows the correct connection of the fuse and
switch of an electric kettle to the mains supply?
(L : live, N : neutral, E : earth)
18.
Which of the following diagrams shows the
magnetic field pattern formed around a flat
circular current-carrying coil, in the plane as
shown?
19.
Two parallel straight wires P and Q
carry equal currents flowing into the
paper. A compass is placed at a point R
where PR = QR. In which of the
following diagrams is the north pole of
the compass needle pointing in the
correct direction?
The effect of the Earth’s magnetic field may be ignored.
page 10 of 16
20.
The above apparatus is used to investigate the force on a current-carrying wire
X, in a magnetic field. When the copper rods are connected to a low voltage
d.c. supply as shown above, what is the moving direction of X?
A.
Move in direction 1.
B.
Move in direction 2.
C.
D.
21.*
Move in direction 3.
Move in direction 4.
Three long, parallel, straight current-carrying wires P, Q and R are placed in
the same plane in air as shown.
P
Q
R
If F is the force per unit length between two long, parallel, straight wires
paced a distance d apart and each carrying a current of 1 A, what is the net
force per unit length acting on the wire R shown?
A.
0
B.
F
C.
2F
D.
3F
page 11 of 16
22.
The figure shows a conducting rod placed on two smooth, parallel, horizontal
conducting rails. A uniform magnetic field is directed into the plane of the
paper. The rod is connected to an external circuit as shown and is initially at
rest.
Which of the following is/are correct?
(1)
When both switches are open, and the rod is given an initial velocity to
the right, the rod will move with a uniform speed.
(2)
A.
B.
C.
When switch X is closed, and the rod is given an initial velocity to the
right, the rod will move with a uniform speed.
When switch Y is closed, the rod will move to the right with a uniform
speed.
(1) only
(3) only
(1) and (2) only
D.
(1) and (3) only
(3)
23.
The following figure shows a coil connected to a galvanometer. A magnet is
initially at rest near the coil.
N
S
Which of the following will generate a north pole at side X of the coil?
(1)
Move the magnet upwards.
(2)
Move the magnet to the right.
(3)
Move the coil to the right.
page 12 of 16
24.
25.
A.
(1) and (2) only
B.
C.
D.
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
A copper wire connected to a galvanometer is placed between the poles of two
powerful magnets as shown above. How should the wire be moved so that a
current is induced in it?
(1)
Moved in direction P.
(2)
Moved horizontally in direction Q.
(3)
Moved down in direction R.
A.
B.
C.
(2) only
(3) only
(1) and (2) only
D.
(1) and (3) only
The figure shows a simple motor.
Which of the following changes can increases the turning effect of the coil?
(1)
(2)
(3)
A.
B.
C.
D.
using a stronger magnet
reducing the resistance of the rheostat
using a coil with a smaller number of turns
(1) and (2) only
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
page 13 of 16
26.
Conducting rods PQ and RS are placed on two smooth, parallel, horizontal
conducting rails. A uniform magnetic field is directed into the plane of the
paper. PQ is given an initial velocity to the right.
Which of the following
statements is INCORRECT?
A.
The induced current is in the direction PQRS.
B.
C.
D.
27.
The magnetic force acting on rod PQ is towards the left.
Rod RS starts moving towards the right.
Rod PQ moves with a uniform speed.
Which of the following particles cannot be deflected by a magnetic field?
A.
α-particles
B.
β-particles
C.
D.
neutrons
protons
28.
It is dangerous if we swallow an alpha source into the body. Why?
A.
It is relatively large in atomic size.
B.
The high penetrating power will hurt the body.
C.
The alpha particle will further decay into carcinogenic material.
D.
The strong ionizing power will affect the body greatly.
29.
Which of the following statements about α,β and γ radiation is correct?
A.
α particles have the highest penetrating power.
B.
β particles have the highest speed.
C.
β particles are deflected in both electric and magnetic field.
D.
γ rays have the highest ionizing power.
page 14 of 16
30.
Different absorbers are placed in turn between a radioactive source and a
Geiger-Muller tube. Three readings are taken for each absorber.
following data are obtained:
The
Count rate / s-1
Absorber
-
200
205
198
paper
197
202
206
5 mm aluminium
112
108
111
25 mm lead
60
62
58
50 mm lead
34
36
34
What type(s) of radiation does the source emit?
A.
B.
C.
D.
31.
 only
 only
 and  only
,  and 
Susan performs an experiment in which a radioactive source is placed closed
in front of a GM counter. The graph below shows the variation of count rate
with time.
What is the half-life of the radioactive substance?
page 15 of 16
32.
A.
4 minutes
B.
C.
D.
5 minutes
6 minutes
7 minutes
In the two decay series, P and Y are two isotopes.
Which of the following pairs of nuclides are isotopes to each other?
(1)
X and R
(2)
Y and S
(3)
A.
B.
C.
D.
33.
On which of the following does the activity of a radioactive source depend?
(1)
(2)
(3)
A.
B.
C.
D.
34.
Z and Q
(1) and (2) only
(1) and (3) only
(2) and (3) only
(1), (2) and (3)
the nature of the nuclear radiation emitted by the source
the half-life of the source
the number of active nuclides in the source
(1) only
(3) only
(1) and (2) only
(2) and (3) only
For a nuclear decay process as shown below, which of the following is correct
for the values of x, y and z?
210
x
A.
B.
C.
D.
x
86
85
83
83
Bi →
y
84
Po +
y
210
210
210
206
0
z
e + energy
z
2
1
-1
-1
page 16 of 16
35.
Which of the following statements about nuclear fission and fusion are
correct?
(1)
Uranium-235 is used in nuclear fission.
(2)
Nuclear fusion occurs in the core of the sun.
(3)
When a light particle split up, huge amount of energy is released.
A.
(1) and (2) only
B.
(1) and (3) only
C.
(2) and (3) only
D.
(1), (2) and (3)
36.
Which of these is a nuclear fusion reaction?
A.
235
92
B.
14
7
C.
2
1
D.
238
92
144
56
U+n →
N+n →
H+
3
1
14
6
H →
U →
234
90
Ba +
90
36
Kr + 2n
C + 11 H
4
2
He + n
Th + α
END OF SECTION A