physics

1 what is a reasonable estimate of the mass of a raindrop?
a 10'kg b 10-'kg c 10°%kg d 10°kg

2 which quantity is a scalar?
a acceleration
b_ force
c kinetic energy
d momentum

3  agalvanometer of resistance 5q is to be used in a null method.

in order to protect the galvanometer from damage due to an excessive initial current, resistors of

resistance 0.5q and 1kq are available.

which arrangement would provide this protection?

a_ the 0.59 resistor in series with the galvanometer

b_ the 0.59 resistor in parallel with the galvanometer and this combination placed in series with
the 1kq resistor

c_ the 1kq resistor in parallel with the galvanometer

d_ the 1kq resistor in parallel with the galvanometer and this combination placed in series with
the 0.5 resistor

4 readings are made of the current j for different voltages v across a fixed resistor. the results are

plotted on a graph to show the variation of i with v.

i e

e
°
e
e
e
e
0
0 vv

what is the best description of the errors in the readings?
a both systematic and random
b_ neither systematic nor random
c_ random only
d systematic only

5 a stone is dropped from a height of 20m above water. the graph shows the variation with time of
the velocity of the stone.
20 shen arenmcncseting
velocity/ms“
0 i i
0 2 4
time/s
which statement describes the approximate position of the stone four seconds after it is
dropped?
a itis at a distance of 10m above the surface of the water.
b_ it is at a distance of 10m below the surface of the water.
c_ itis at a distance of 20m below the surface of the water.
d_itis at a distance of 30 m below the surface of the water.

6 acar xis travelling at a constant speed u along a straight road. at time t= 0 a second car y isa
distance dp behind car x and travelling at a speed v in the same direction. speed v is less than
speed u.

vv u
car y , car x .
acts je
| dy
 ——_
at time t = 0 car y begins to accelerate with a constant acceleration.
car y overtakes car x at time f= t.
which graph could best show the variation with time t of the distance d between the cars?
a b cc d
d \ qd es d, ~ qd \

8 an astronaut has a weight of 660 n when she is standing on the earth’s surface.
the acceleration of free fall on the surface of mars is 3.71ms~.
what would be the weight of the astronaut if she stood on the surface of mars?
a 67.3n b 178n c 250n d 660n

9 amass mm, travelling with speed u; collides with a mass mz travelling with speed uz in the same
direction. after the collision, mass m, has speed v; and mass mz has speed v2 in the same
direction. the collision is perfectly elastic.

before the collision after the collision
which equation is not correct?
a mu? = myv,? = mov2? — mou”
bo ovo t+ up = vy + uy
c omi(u1 — v4) = ma(v2 — ur)
domus — v4)? = ma(u2 — v2)?

10 the diagrams show a negative electric charge situated in a uniform electric field and a mass
situated in a uniform gravitational field.
> sc
—_-- ss
— tt
o© charge o mass
a —_.— sss oe
sal =
> a
uniform electric field uniform gravitational field
which row shows the directions of the forces acting on the charge and on the mass?
| charge | mass
a oo o—-
be) = toes
, t
: y

11 a bicycle pedal is connected to a pivot by a metal bar, as shown.
force 60n
pedal
bar i ‘
12cm
20cm
pivot /
s 16cm a

the force on the pedal is 60 n downwards.
what is the moment of this force about the pivot?
a 7.2nm b 9.6nm c 12nm d 1200nm

12 a thin horizontal beam xy is freely hinged at point y to a vertical wall. the beam is held
stationary by a cable xz which is attached to the wall at point z.
z
iy — wall
cable
hinge
xx
beam 7
ww

the beam supports a weight w at point x. the forces in the cable and the beam are fc and fz
respectively.
which vector triangle represents the forces acting on point x?

a b cc d

fg fp fe fp

13 a pipe, open at one end, floats in a liquid as shown.
0.40m
0.30m
area 0.012 m?
the cross-sectional area of the pipe is 0.012m*. the weight of the pipe is 32n.
what is the density of the liquid?
a 680kgm* b 910kgm° c 6700kgm* d = 8900kgm®

14 during an interval of time, fuel supplies energy x to a car.
some of this energy is converted into kinetic energy as the car accelerates.
the rest of the energy y is lost as thermal energy.
what is the efficiency of the car?
a ly b <y¥ c x d x

15 in which situation is work done on an object?
a_ the object slides with a constant velocity along a horizontal frictionless surface in a vacuum.
b_ aperson holds the object at arm’s length and at a fixed height above the ground.
c a person pushes the object up a frictionless ramp.
d_ the stationary object floats partially submerged in water.

16 a spring is attached at one end to a tixed point. a mass is then hung from the other end of the
spring. the spring has extension x when the system is in equilibrium.
oy
po
spring tension iy,
acs s |
sr
1 0 =
x 0 a
paonteos extension
the variation of the tension in the spring with its extension is shown on the graph.
which statement is correct?
a area spr represents the energy stored in the spring which cannot be recovered.
b area spqr represents the energy stored in the spring which can be recovered.
c area spq represents the loss of gravitational potential energy of the mass due to the
extension of the spring.
d area sqr represents the elastic potential energy stored in the spring.

17 an escalator in an underground station has 25 people standing on it and is moving with a speed
of 4.3ms"'. the average mass of a person is 78kg and the angle of the escalator to the
horizontal is 40°.

what is the minimum power required to lift these people?
a 5.4kw b 6.4kw c 53kw d 63kw

18 an elastic cord of unstretched total length 16.0cm and cross-sectional area 2.0 x 10°°m’ is held
horizontally by two smooth pins a distance 8.0 cm apart.
the cord obeys hooke’s law. a load of mass 0.40kg is suspended centrally on the cord. the
angle between the two sides of the cord supporting the load is 60°.
, unstretched cord : : ‘
pin pin pin. 8.0cem - pin
$$$!
ns a 6 2
8.0cm
cord
8.0cm
|
h— mass 0.40kg
|
what is the young modulus of the cord material?
a 5.7x10°pa b 1.1x10°pa c 2.3x10°pa d 3.9x10°pa

19 a student is investigating the mechanical properties of a metal. he applies different loads to a
long thin wire up to its breaking point, and measures the extension of the wire for each load. he
then plots a graph of stress against strain.

stress 4
‘6
/10°pa 3
2
1
0
0 10 20 30 40
strain/10~°
the student repeats the experiment with a wire made from the same metal, with twice the original
length and half the diameter.
which graph is obtained?
a b
stress 4 stress 4
6 6
/10°pa 3 /10°pa 3
2 2
1 1
0 0
0 20 40 60 80 0 10 20 30 40
strain/10° strain/10°
cc d
stress 16 stress 16
6 6
/10°pa 12 /10°pa 12
8 8
4 4
0 0
0 20 40 60 80 0 10 20 30 40
strain/10° strain/10°

20 which statement describes what is meant by the plastic deformation of a material?
a_ it always obeys hooke’s law.
b_ it does not return to its original length when the extending force is removed.
c_ it never obeys hooke’s law.
d_ it returns to its original length when the extending force is removed.

21 a transverse wave is moving along a rope. two points x and y on the rope are a quarter of a
wavelength apart from each other.
which statement is not possible for the two points x and y at any instant?
a they are both stationary.
b_ they are displaced in opposite directions from their equilibrium position.
c_ they are moving in opposite directions.
d_ they both have displacements of the same magnitude from their equilibrium positions.

22 two progressive waves meet at a fixed point p. the variation with time of the displacement of
each wave at point p is shown in the graph.
. lt os tt ee ee
displacement [hattie eheeeee eee eee seth
sp 4
ncee ee ee ene eee eee ecs eee een
essere ee eee ee eere eee eee eae eere eee eee eea
22n se ey a ne
pcenreeeeeeeeeeeeeaceeee eee eeeeepeezepnceeeeee eee
0 serre ner bes ue eee se eee ee eee
0 found ds | das | pig 07) be on fo 1.2
fleeee nettles eo st
a a a ime/s da
pep se eer in ae eer
peseu ures laes nung di beans cuca ueez40 gna queems esus;aeancea|
pp tpt rrr yy rrr rr seer | pe er
what is the phase difference between the two waves at point p?
a 45° b 90° c 135° d 180°

23 a microphone connected to the y-plates of a cathode-ray oscilloscope (cro) is placed in front of
a loudspeaker. the trace on the screen of the cro is shown.
pit tty yt
p| tt vin i
kt tt at he
att tat at i
alt det tal i
py | ft | a
eweseen
pete et tt
=>
icm
the time-base setting is 0.5ms cm" and the y-plate sensitivity is 0.2mvcm™.
what is the frequency of the sound from the loudspeaker and what is the amplitude of the trace
on the cro?
ce [a
/hz /mv
a 330 0.6
b 330 1.2
cc 670 0.6
d 670 1.2

24 the diagram shows an experiment to produce a stationary wave in an air column. a tuning fork,
placed above the column, vibrates and produces a sound wave. the length of the air column can
be varied by altering the volume of the water in the tube.

tuning fork ——-_____
air column
water
tap
the tube is filled and then water is allowed to run out of it. the first two stationary waves occur
when the air column lengths are 0.14m and 0.42m.
what is the wavelength of the sound wave?
a 0.14m b 0.28m c 0.42m d 0.56m

25 a stationary person measures the speed and wavelength of the sound from a horn on a
stationary vehicle. the person then repeats the measurements when the vehicle is approaching
at a constant speed.

which row describes the measured wavelength and the measured speed of the sound wave from
the moving vehicle when compared with the sound wave from the stationary vehicle?
wavelength of speed of
the sound wave the sound wave
a longer greater
b shorter greater
c longer same
d shorter same

26 the table shows the wavelengths of five electromagnetic waves.
which row correctly identifies the principal radiation for each of these wavelengths?
[etm [om | otm [tom [om
a gamma-ray x-ray infrared microwave radio wave
b radio wave microwave infrared x-ray gamma-ray
cc radio wave microwave ultraviolet infrared x-ray
d x-ray infrared ultraviolet microwave radio wave

27 two progressive waves meet at a point.
which condition must be met for superposition of the waves to occur?
a_ the waves must be coherent.
b_ the waves must be of the same type.
c_ the waves must be travelling in opposite directions.
d the waves must meet in phase.

28 a hill separates a television (iv) transmitter trom a house. ihe transmitter cannot be seen trom
the house. however, the house has good tv reception.
hill
a
:
tv transmitter house
by which wave effect at the hill could the tv signal reach the house?
a_ coherence
b_ diffraction
c interference
d_ reflection

29 the diagram shows an arrangement for demonstrating two-source interference using coherent
light of a single wavelength 2.
| p second bright fringe
x first bright fringe
* | q_ central bright fringe
light of ¥
wavelength 2 30m not to
scale
slits
screen
an interference pattern is observed on a screen 3.0m away from the slits x and y, which have a
separation of 1.0mm.
the central bright fringe is at q, and the second bright fringe from the centre is at p.
what is the distance between q and p?
a 6.0x10°a
b 3.0x 104
c 6.7x1042
d 3.3x10%a

30 light of wavelength 4 is incident normally on a diffraction grating. the angle between the
second-order maximum and the normal to the grating is @ the variation with sin 0 of 2 is shown
on the graph.

750 2 eee,
5 a 6
eee eee eee eee eee eee
ai 0-° td i id i id a i gl ga ie?
= gasgssric ccr crrcren me nslsea
eeeeeeeeeeeeeeeeeeeee ae eeeeeh
500 eee fry
sed eeetocattoeesdtcetitoctat
eere eere eee eere h
cee ete cerro
eeeee eee cee eee reer
eoccecc a
250 -leeeeeeeee pae eee]
eee ees
htt ett ttt
coca pepe eee eee]
eco cee eee eee
eco cee eee eee
8 ee y
dz eee eee eee eee
(e) 4) 0m 0 a a a a ta a a
0 0.2 0.4 0.6
sin @
how many lines per millimetre are on the diffraction grating?
a 400mm" b 625mm‘ c 800mm" d 1250mm"'

31 adipole is a pair of charges of equal magnitude, one negative and one positive. the electric field
of a dipole is shown below.
in which direction does the force act on an electron when at point x?
xx
a a d

32 a charged oil droplet of mass m is falling, initially freely, in a vacuum between two horizontal
metal plates that are separated by a distance x.
a potential difference (p.d.) v is then applied across the plates. this results in the oil droplet
continuing to accelerate downwards but with a reduced acceleration a.
the polarity of the applied p.d. is then reversed so that the direction of the electric force on the
droplet is reversed. this results in the downwards acceleration of the oil droplet increasing to 3a.
what is the magnitude of the charge on the oil droplet?
a max b 2/max cc 3max dp 4max

vv vv vv vv

33 the number density of free electrons in copper is 8.0 x 10°° m~.
a copper wire has diameter 0.42 mm.
what is the average drift speed of the free electrons in the wire when the current in the wire is
0.57a?
a 8.0x10"'ms"
b 3.2x10ms"
c 8.0x10°ms™
d 3.2x10‘*ms"*

34 an electric kettle is rated at 2.0kw, which describes the power supplied to the heating coil in the
kettle.
the coil has a resistance of 5.0kq.
what is the current in the coil?
a 0.40a b 0.63a c 1.6a d 2.5a

35 a conductor consists of three wires connected in series. the wires are all made of the same
metal but have different cross-sectional areas. there is a current j in the conductor.
ps conductor y
i ra
+. (eet
point y on the conductor is at zero potential.
which graph best shows the variation of potential v with distance along the conductor?
vv
a
0 distance
x ¥
vv
b
0 distance
xx ¥
v
cc
0 distance
xx 4
vv
d
0 distance
4 ¥

36 accell of electromotive force (e.m.f.) e and internal resistance 0.50q is connected to a resistor of

resistance 4.7q.

ie

1 0.50q |

4.72

the maximum power that can be dissipated by the resistor without overheating is 0.50 w.
what is the maximum value of e for the resistor not to overheat?
a 14v b 1.5v cc 1.7v d 2.9v

37 kirchhoffss first and second laws link to the conservation of physical quantities.
which quantities do they link to?
[[tstiow | secondiow |

a charge energy
b charge momentum
cc energy charge
d energy momentum

38 in the circuit shown, x is a variable resistor whose resistance can be changed from 5.0q to
500q. the electromotive force (e.m.f.) of the battery is 12.0v. it has negligible internal
resistance.

40q
——
120w
—
x output
what is the maximum range of values of potential difference across the output?
a 1.3v to 11.1v
b 1.3v to 12.0v
c 1.5v to 11.1v
d 1.5v to 12.0v

39 an unstable nucleus goes through successive decays to become a final, stable nucleus.

the initial nucleus and the final nucleus are isotopes of each other.
how many « and f particles could have been emitted during the decay sequence?
==

a 1 0

b 1 2

cc 2 0

d 2 1

40 a hadron has a charge of —e and is composed of three quarks.
what could be the quark composition of the hadron?
a b cc d
key
(s) ©) @) () ©) ©) (@) (@)) — u=up quark
6) 6) g) o s = strange quark

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