physics

1 acar is travelling at a speed of 20ms™. the table contains values for the kinetic energy and the
momentum of the car.

which values are reasonable estimates?
kinetic energy momentum

lj /kgms“'

a 3 x 10° 3 x 104

b 3 x 10° 5 x 10°

c 2 x 10’ 3 x 104

d 2 x 10’ 5 x 10°

2  whatis the unit of resistance when expressed in si base units?
a kgm’?s?a7
b kgm’?s°a?
c kgms?a"
d kgms°a"*

3. which list contains both scalar and vector quantities?
a acceleration, momentum, velocity, weight
b area, current, force, work
c_ distance, kinetic energy, power, pressure
d_ mass, temperature, time, speed

4 vectors p and q are drawn to scale.
p q
which diagram represents the vector (p + q)?
a b
oe \
cc d
il \

5 students take readings of the volume of a liquid using three different pieces of measuring
equipment x, y and z.
the true value of the volume of the liquid is v.
the students’ results are shown.
xx ¥ z
a

6 a sprinter runs a 100m race. ihe sprinter has a constant acceleration trom rest of 2.05mms ~ until
reaching a speed of 10ms™". the speed then remains constant until the end of the race.
which time does it take the sprinter to run the race?
a 89s b 10s cc 12s d 14s

7  aresultant force of 10n acts on a body for a time of 2.0s.
which graph could show the variation with time t of the momentum p of the body?
20
plkgms“
15
a
10 b
an
0
0 1.0 2.0
tis

8 the acceleration of free fall on the surface of planet p is one tenth of that on the surface of
planet q.
on the surface of p, a body has a mass of 1.0kg and a weight of 1.0n.
what are the mass and the weight of the same body on the surface of planet q?
| | mass on q/kg weight on q/n
a 1.0 0.1
b 1.0 10
cc 10 10
d 10 100

9 two bodies travelling along the same straight line collide in a perfectly elastic collision.
which statement must be correct?
a the initial speed of one body will be the same as the final speed of the other body.
b_ the relative speed of approach between the two bodies equals their relative speed of
separation.
c_ the total momentum is conserved but the total kinetic energy will be reduced.
d one of the bodies will be stationary at one instant.

10 the diagram shows two identical spheres x and y.
—— v
x ¥

initially, x moves with speed v directly towards y. y is stationary. the spheres collide elastically.
what happens?
ee ee

a moves with speed 3v to the right moves with speed zv to the right

b moves with speed v to the left remains stationary

cc moves with speed 7v to the left moves with speed 7v to the right

d stops moves with speed v to the right

11 a positively-charged particle of negligible mass, moving at constant velocity vin a vacuum, enters
a uniform electric field between two parallel plates, as shown.
_positive plate
vv
+ @— >
~negative plate
a short time later, the particle is at the position shown.
_positive plate
e
™negative plate
which diagram represents the force or forces acting on the particle?
a b cc d

12 a uniform rectangular board is supported by a frictionless pivot at its centre point p.
r
a 2.5f
20cm
p
qa
f

two forces act in the plane of the board. force f acts at corner q and force 2.5f acts at
corner r. the perpendicular distance between the line of action of force f and point p is 20cm.
the board is in equilibrium.
what is the area of the board?
a 160cm? b 320cm? c 640cm? d 1600cm?

13 akite is in equilibrium at the end of a string, as shown.
kite
string
ww

the kite has three forces acting on it: the weight w, the tension 7 in the string, and the force f

from the wind.

which vector diagram represents the forces acting on the kite?

a b cc d
f f

sl sal f t

14 the density of the air in the atmosphere decreases as the height h above the surface of the earth
increases.
which graph best shows the variation with height h of the pressure p of the air?
a b cc d

15 a bungee jumper on a platform over a river is attached to an elastic rope that is 20m long when
unstretched. he falls towards the river and his lowest point is 30 m below the platform.
the initial gravitational potential energy of the jumper is transferred to other forms during the
jump.
which other forms of energy do the jumper and rope have when the jumper has fallen half-way
and when he is at the lowest point of his jump?
| | half-way lowest point
a | kinetic energy and elastic potential energy | kinetic energy and elastic potential energy
b kinetic energy and elastic potential energy elastic potential energy only
cc kinetic energy only kinetic energy and elastic potential energy
d kinetic energy only elastic potential energy only

16 a cylinder contains a fixed mass of gas. the gas, at a constant pressure of 1.3 x 10°pa, expands
from a volume of 900 cm? to a volume of 1100.cm®.
what is the work done by the gas during this expansion?
a 26j b 130j c 2600j d 13000j

17 an object is thrown into the air.
which graph shows how the gravitational potential energy e, of the object varies with height h
above the ground?
a b cc d
e. | es | e. | | e. |
0 h 0 h 0 h 0 h

18 a car of mass 1800kg accelerates along a horizontal road so that its speed increases from
20ms™ to 25ms" ina time of 5.4s.
what is the average useful power output of the car’s engine?
a 4.2kw b 38kw c 120kw d 1100kw

19 a variable force is applied to ensure that a constant power is supplied to a train.
which graph best shows the variation of the force f applied with the velocity v of the train?
a b cc d
a

0-—————————————— ———_——— o-————___> ——\———_
0 4 0 v 0 vv 0 v

20 a metal cylinder is able to withstand a compressive force of 4.0 kn without deforming plastically.
the cylinder has cross-sectional area a and would be at its elastic limit when a stress o is
applied.

what is a possible pair of values for a and a?
[aime oruea |

a 1.5x 10° 50

b 1.5x 10° 80

c 7.5x 10° 50

d 7.5x 10° 80

21 avwire has both elastic and plastic properties. when it is slowly loaded, its extension varies with
load as shown by line oxy. the removal of the load is represented by line yz. this creates areas
p, q and r on the graph.

ra im ees. ag
load x
p
ro}
9
0 i
0 zz extension
which area represents the maximum elastic potential energy stored in the wire?
a p bq c q+r dr

22 a progressive wave on a wire has a frequency of 10hz. two points on the wire, separated by a
distance of 0.25m, have a phase difference of 22.5°.
what is the maximum speed of the wave?
a 2.5ms* b 10ms* c 20ms* d 40ms"*

23 when a guitar string is plucked, it causes a longitudinal sound wave in the air, as shown.
pe ee "ce twee a2
i a a
beh . ef a eee = «2
reasee og ag on aren * oe s po « “
pash, e* eo ty *, % .* ° prt ol ee ee . pu
fees a ere? £ :2
soe te te 8 te 5% ts oe
ats att oven cee + ie en aay oo) . :
* a6 *: . icf fae ° a e,
0.0 0.2 0.4 0.6 0.8
distance/m

the speed of sound in the air is 340ms"'.

what is the approximate frequency of the sound wave shown?

a 430hz b  680hz c 1100hz d 1400hz

24 the sound from a loudspeaker placed above a tube causes resonance of the air in the tube.
a stationary wave is formed with two nodes and two antinodes as shown.
her loudspeaker
60cm | \
the speed of sound in the air is 340ms™.
what is the frequency of the sound?
a 430hz b  570hz c 850hz d 1700hz

25 a police car has a two-tone siren emitting sound of frequencies of 700 hz and 1000 hz.
the police car is travelling at a speed of 40.0ms™' towards a stationary observer. the speed of
sound in the air is 340ms"'.
what is the difference between the two frequencies of the sound that is heard by the observer?
a 268hz b  300hz c 335hz d 340hz

26 asurveyor’s device emits a pulse of light. the light is reflected from a wall 150m away.
what is the time taken for the pulse to travel from the device to the wall and then back to the
device?
a 0.05ns b 0.10ns c 0.50us d 1.0pus

27 progressive sound waves of wavelength 20cm enter the air columns in a closed pipe p and an
open pipe q. the lengths of the pipes are shown.
p q
—_ —““~ a al
35cm 50cm
in which pipe or pipes are stationary waves formed?
a pandq
b_ ponly
c qonly
d_ neither p nor q

28 what happens when waves pass through a gap equal to their wavelength?
a_ there is diffraction and the wavelength decreases.
b_ there is diffraction and the wavelength stays the same.
c_ there is no diffraction and the wavelength decreases.
d_ there is no diffraction and the wavelength stays the same.

29 two sources of microwaves p and q produce coherent waves with a phase difference of 180°.
the waves have the same wavelength i.
oc eeeeeneeeteesst@s
eee ile
qe
at the point s there is a minimum in the interference pattern produced by waves from the two
sources. the distance (qs — ps) is called the path difference.
in the expressions shown, n is an integer.
which expression represents the path difference?
a nm b im c (n+ tyr d (2n+4)r

30 a parallel beam of monochromatic light of wavelength 4 is incident normally on a diffraction
grating g. the angle between the directions of the two second-order diffracted beams at p; and
at p2is a, as shown.

p,
g
light | a
p,
what is the spacing of the lines on the grating?
sina sina sin(a/2) sin(a/2)

31 a flat plate is positively charged and a curved plate is negatively charged.
which diagram shows the electric field lines between the two plates?
a b
+ + + + + +
cc d
+ + + + + +

32 two parallel metal plates are connected to a d.c. supply, as shown.
—_—_
the two plates are moved towards each other at constant speed.
it may be assumed that the electric field between the plates is uniform.
point p is mid-way between the two plates.
which graph shows the variation with time t of the electric field strength e at point p?
a b cc d

33 which two units are used to define the coulomb?
a ampere and second
b ampere and volt
c_ volt and ohm
d_ volt and second

34 an electrical device of fixed resistance 20 is connected in series with a variable resistor and a
battery of electromotive force (e.m.f.) 16v and negligible internal resistance.
16v
200
device
what is the resistance of the variable resistor when the power dissipated in the electrical device
is 4.0w?
a 160 b 360 c 440 d 600

35 avwire of length l has resistance r. the cross-section of the wire is circular with radius r.
a second wire, also of circular cross-section, and of the same material, has resistance +r.
what could be the radius and the length of the second wire?
| eas | ena

l,

a £ a
2 2

fr £

b — —
v2 2

cc rjf2 2l
d 2r 2l

36 a battery of negligible internal resistance may be connected between any two points p, q, r and
s of the network of resistors shown.
p 3.00 q
6.0q 1 5.0q
s 4.00 5b
which connections will give the largest current and the smallest current in the battery?
| | largest current | smallest current
a pq pr
b pq qs
cc rs pr
d rs qs

37. kirchhoff’s second law is a consequence of a basic principle.

what is this principle?

a_ the charge flowing in an electric circuit is conserved.

b_ the energy in an electric circuit is conserved.

c_ the sum of the electric currents entering a point in an electrical circuit is equal to the sum of
the electric currents leaving that point.

d_ the sum of the potential differences in a circuit is equal to the sum of the products of the
current and resistance.

38 two cells are investigated using a potentiometer. at the balance point, cell x gives a reading of
44cm and cell y gives a reading of 70cm.
6v 6v
r r
its ti tal tl ll tld il
44cm 70cm
cell x cell y
galvanometer galvanometer
which statement is not correct?
a_ a potentiometer balance point results in zero current through the galvanometer.
b_ at the balance point, the current through resistor r in both circuits is the same.
c_ the electromotive force (e.m.f.) of cell x is larger than that of cell y.
d_ the value of the e.m.f. of each of the cells x and y is less than 6v.

39 a proton in a nucleus undergoes §* decay. one of the products is a neutron.
what are the other products?
a anelectron and a neutrino
b_anelectron and an antineutrino
c_ apositron and a neutrino
d_ apositron and an antineutrino

40 a certain type of hadron has zero charge. it is composed of a down quark, a strange quark and
one other quark.
what could be the other quark?
a up
b down
c strange
d_anti-strange

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