physics

1 asheet of gold leaf has a thickness of 0.125 um. a gold atom has a radius of 174 pm.
approximately how many layers of atoms are there in the sheet?
a 4 b 7 c 400 d 700

2. the drag coefficient cy is a number with no units. it is used to compare the drag on different cars
at different speeds. cy is given by the equation
aa of
v"pa
where f is the drag force on the car, pis the density of the air, a is the cross-sectional area of the
car and vis the speed of the car.
what is the value of n?
a 1 b 2 cc 3 d 4

3 a student measures the current through a resistor and the potential difference (p.d.) across it.
there is a 4% uncertainty in the current reading and a 1% uncertainty in the p.d. reading. the
student calculates the resistance of the resistor.

what is the percentage uncertainty in the calculated resistance?
a 0.25% b 3% c 4% d 5%

4 a student applies a potential difference v of (4.0+0.1)v across a resistor of resistance r of

(10.0 + 0.3)q for a time t of (50 + 1)s.
the student calculates the energy e dissipated using the equation below.

2. 2

f= vet _ 4.07x50 = 80j

r 10.0
what is the absolute uncertainty in the calculated energy value?
a 1.5j b 3j cc 6j d 8j

5 the velocity of an object changes with time t as shown.
velocity
0
| t
which graph best shows the variation with time t of the displacement s of the object?
a b
0 0
0 t 0 t
cc d
ss s
0 0
0 t 0 t

6 a projectile is launched at an angle to the horizontal at time t= 0. it travels over horizontal
ground, as shown.
path of projectile
ground
assume that air resistance is negligible.
which graph best shows the variation with t of the speed of the projectile from when it is launched
to when it lands on the ground?
a b
speed speed
0 0
0 t 0 t
cc d
speed speed
0 0
0 t 0 t

7 a sky-diver falls vertically from a helicopter and reaches constant (terminal) velocity. the graph
shows the variation with time t of the speed v of the sky-diver.
vv
0
0 t
which graph shows the variation with time t of the distance d fallen by the sky-diver?
a b cc d

8 a tennis ball of mass 595g is travelling horizontally with a speed of 30ms™. the ball makes
contact with a wall before rebounding in the horizontal direction with a speed of 20ms™". the ball
is in contact with the wall for a time of 5.0 x 10°°s.

what is the average force exerted on the wall by the ball?
a 110n b 220n c 330n d 550n

9 an elastic collision occurs between two bodies x and y. the mass of body x is m and the mass
of body y is 4m. body x travels at speed v before the collision and speed = in the opposite
direction after the collision. body y is stationary before the collision.

3v
v 5
ee el =_ a el
m 4m m 4m
before after
what is the kinetic energy of body y after the collision?
a 2 my’ b 34 my? c 16 my? dd 1mv?
10 50 50 5

10 the density of water is 1.0gcm™ and the density of glycerine is 1.3gcm™*.
water is added to a measuring cylinder containing 40 cm* of glycerine so that the density of the
mixture is 1.1gcm™*. assume that the mixing process does not change the total volume of the
liquid.
what is the volume of water added?
a 40cm? b 44cm* c 52cm* d 80cm?

11 an astronaut throws a stone horizontally near to the surface of the moon, where there is no
atmosphere.
which row describes the horizontal and vertical forces acting on the stone after release?
a non-zero and constant constant
b non-zero and constant decreasing
cc zero constant
d zero decreasing

12 a cylindrical block of wood has cross-sectional area a and weight w. it is totally immersed in
water with its axis vertical. the block experiences pressures p; and pp at its top and bottom
surfaces respectively.

which expression is equal to the upthrust on the block?
a (pp — pr)

bi (pp- pa

c (pp - pa - w

d (py- p)a+w

13 a uniform diving-board is held by two fixed rods at points p and q. a person stands at end r of
the diving-board, as shown.
n
rod - q i
prod r
the forces exerted by the rods on the board are vertical. the board remains in equilibrium as the
person slowly moves towards point q from end r.
which row describes the changes to the forces exerted by the rods on the board?
[| bees [eat
a decreases decreases
b decreases increases
cc increases decreases
d increases increases

14 iwo forces, each of magnitude f, act in opposite directions on a rod.
f
p
1 d d
f

each force acts on the rod at a distance d from the pivot p.
what is the torque of this couple about p?
a 0 b fxd c 2fxd d 2fx2d

15 the vector diagram shows three coplanar forces acting on an object at p.

ptet tete et et
pp tt tp eant tt tt
ppe ete eee ey yy
pt ttt fey
lt tt pee ant tt
pit yee ee
bnd ue

the magnitude of the resultant of these three forces is 1n.

what is the direction of this resultant force?

a b na c™ dy

16 in ‘normal driving conditions’, an electric car has a range of 150 km. this uses all of the 200 mj of
energy stored in its batteries.
with the batteries initially fully charged, the car is driven 100 km in ‘normal driving conditions’. the
batteries are then recharged from a household electrical supply delivering a constant current of
13.0a at a potential difference of 230v.
what is the minimum time required to recharge the batteries?
a 0.95 hours
b 12.4 hours
c 18.6 hours
d = 27.9 hours

17 the diagram shows a ball of weight w hanging in equilibrium from a string.
z
t
string
ball
p
= =o
rod

ww
the string is at an angle @to the vertical. the tension in the string is t. the ball is held away from
the wall by a horizontal force p from a metal rod.
what is the relationship between the magnitudes of 7, p and w?
a p=tcos@ and w=tsing
b t=p+w
cc t=p?+w
d w=ptan@ and w=tcos@é

18 a steel sphere is dropped vertically onto a horizontal metal plate. the sphere hits the plate with
speed u, leaves it at speed v, and rebounds vertically to half of its original height. ignore air
resistance.

which expression gives the value of ae
1 1 1 1
a — bs cc — d 1-—
2 2 v2 v2

19 acar of mass 500kg is at rest at point x on a slope, as shown.
the car’s brakes are released and the car rolls down the slope with its engine switched off. at
point y the car has moved through a vertical height of 30m and has a speed of 11ms™.
~ e> mass = 500kg
- ~~ as speed = oms
- scone x
ss lp
30m ny end
oo) es speed = 11ms1
“sq
ca scan ac ae scast ceca as eseamans armani te ga y
what is the energy dissipated by frictional forces when the car moves from x to y?
a 3.0x104j b 1.2x10°j c 1.5x10°j d 1.8x10°j

20 an elastic material with young modulus e is subjected to a tensile stress s. hooke’s law is
obeyed.
what is the expression for the elastic energy stored per unit volume of the material?
2 2,
a £. a & g = » =
2s2 ss? e 2e

21 +|he grapn shows the lengin of a spring as it is stretched by an increasing load.
15 pie ee hh ne ee
i a a a nt ln gg gi a saa ll a
length/cm i i aa gd nt gab gn gg i cl dg a a
a ca a el ni ga gs al a dl a
sers se ee =. 2 eee eee
sss
sss
sss 2 ee
ree ee eee eee
10 [eee eee eee eee eee eee eee
es a 6 al
es see eee eee eee eee ess eee eee eee
pt a 9 0 oa
sssr re eee bee eee ee eee
ss
a 0 op pe |
eee eee eee eee eee eee eee
5 eere eee eee eee eee eee eee eee
ss
eee eee eee eh
sss
s00
ss
ddt dr ea
ss
0 ped ree hes ree
0 0.1 0.2 0.3 0.4 0.5
load/n
what is the spring constant of the spring?
a 0.080nm* b_ 0.13nm* c 2.7nm* d 8.0nm"*

22 two lasers emit light in a vacuum. one laser emits red light and the other emits green light.
which property of the two laser beams must be different?
a amplitude
b_ frequency
c intensity
d_ speed

23 the diagram shows the screen of a cathode-ray oscilloscope (c.r.o.) displaying a wave.

ttt ttt tt
in| | tan [i
pi an | iy a t/t
p| wt pt wat yt
| | ina t lny tf
serre

the time-base of the c.r.o. is set at 10 ms/division.

what is the frequency of the wave?

a 0.24hz b 4.2hz c 12hz d 24hz

24 a string is fixed at one end and the other end is attached to a vibrator. the frequency of the
vibrator is slowly increased from zero. a series of stationary waves is formed. assume that for a
stationary wave there is a node at point p.

string
p
: fixed
what are the first five wavelengths of the stationary waves that could be formed?
a 26,0624 94 ob
1.52 3 4 =5
b gh oh oh ot ot
2 3 4 5 6
c 4£ ,4£ 4h gh gk
1 2 3 4 5
pd 44 4h gh gl gl
13 5 7 9q

25 which region of the electromagnetic spectrum has waves of wavelength 1000 times smaller than
the wavelength of visible light?
a infra-red
b- microwaves
c ultraviolet
d x-rays

26 the diagram shows apparatus for the measurement of the frequency of a sound wave.
oo j
microphone souree
of sound

metal

plate
sound of the unknown frequency is reflected back from a metal plate. a microphone placed at a
distance d from the metal plate detects the sound intensity. a minimum intensity is detected with
d=12.0cm. the plate is moved further away from the microphone until the next minimum is
detected with d = 15.0cm.
the speed of sound in air is 336ms"'.
what is the frequency of the sound?
a 56hz b 112hz c 5600hz d 11200hz

27 anastronomer observes the light from a star that is moving away from the earth.
for the observed light, what has been increased due to the star’s motion?
a amplitude
b_ frequency
c speed
d_ wavelength

28 the diagram shows a stationary wave, at time ft = 0, that has been set up on a string fixed
between points p and s.
x
xx ¥
p q r is)
a
the nodes of the stationary wave occur on the string at p, q, r and s. point x is moving down at
time t = 0. the points on the string vibrate with time period t and maximum amplitude 2cm.
the displacement s is positive in the upward direction.
which graph best shows the variation with t of the displacement s of point y on the string?
a b
2 2
s/cm s/cm
0 0
0 ff 0 ct
|
-2 -2
cc d
2 2
s/cm s/cm
0 0
0 rt it 0 x tt
|
-2 -2

29 a two-source interference experiment uses the apparatus shown.
ea
lamp
single double screen
slit slit

what is the main purpose of the single slit?
ato make a narrow beam of light
b_ to make the same amplitude of light incident on each slit
c to provide coherent light
d to provide monochromatic light

30 two large parallel metal plates x and y are situated in a vacuum as shown.
plate x ii
positively
*—~ charged
particle
plate y
plates x and y carry equal and opposite charges.
what happens to the force on a positively charged particle as it moves from plate x to plate y?
a_ lt decreases because the positively charged particle is moving away from the positively
charged plate.
b_ it decreases because the positively charged particle is moving in the direction of the electric
field between the plates.
c_ it increases because the positively charged particle is moving closer to a negatively charged
plate.
d_ it remains constant because the positively charged particle is in the uniform electric field
between the plates.

31 four diagrams representing the electric field between two oppositely-charged point charges are
shown.
which diagram correctly shows the electric field lines?
a b
> ko
cc d
ee ks

32 the power output of an electrical supply is 2.4kw at a potential difference (p.d.) of 240v. the
two wires between the supply and a kettle each have a resistance of 0.50, as shown.
supply kettle
0.500
240v
2.4kw oe
0.500
what is the power supplied to the kettle and what is the p.d. across the kettle?
| | power/kw p.d./v
a 2.3 230
b 23 235
cc 2.4 230
d 24 235

33 which graph shows the variation of voltage v with current j for a semiconductor diode?
a b
vv | vv
——0
0 i i
cc d
vv | vv
——0
0 i i

34 four different resistors are arranged as shown.
a current of 1.5a enters the network at junction x and leaves through junction y.
1.5a
y
70q 600
15a x

50q 300
what is the current in the resistor of resistance 30. q?
a 0.21a b 0.50a c 0.75a d 1.0a

35 a cell of constant electromotive force drives a current j through an external resistor of
resistance r. the terminal potential difference (p.d.) across the cell is v.
a
earner
i ce
r
when the internal resistance r of the cell increases, what is the effect on v and on i?
pf oovy ft
a decreases decreases
b decreases increases
cc increases decreases
d increases increases

36 in the circuits shown, the batteries are identical and all have negligible internal resistance. all of
the resistors have the same resistance. the diodes have zero resistance when conducting and
infinite resistance when not conducting.

in which circuit is the current in the battery greatest?
a b
cc d

37 a thermistor is an electrical component with a resistance that varies with temperature. a
thermistor t is used in a fire alarm system. the alarm is triggered when the potential difference
between x and y is 4.5v.

12v
t ; 150q
xx y
what is the resistance of t when the alarm is triggered?
a 900 b 1500 c 2500 d 4000

38 in the a-particle scattering experiment, a beam of a-particles is aimed at a thin gold foil. most of
the a-particles go straight through or are deflected by a small angle. a very small proportion are
deflected through more than 90°, effectively rebounding towards the source of the a-particles.
which conclusion about the structure of atoms cannot be drawn from this experiment alone?

a_ most of the atom is empty space.

b_ most of the mass of an atom is concentrated in the nucleus.
c_ the nucleus contains both protons and neutrons.

d_ the nucleus is charged.

39 radon-211, “4,rn, francium-210, “,7fr, and radium-212, “3;ra, are three nuclides.
how many neutrons does each nuclide have in its nucleus?
| | radon-211 francium-210 radium-212
a 86 87 88
b 125 123 124
cc 211 210 212
d 297 297 300

40 a neutron is composed of one up (u) quark and two down (d) quarks. when the neutron decays
to a proton, there is b-emission.
what is the change in the quark structure of the neutron due to the b-emission?
(the symbol for a neutrino is ve and for an antineutrino is ve )
a d>utfbp + ve
bd>u+pty,
c urdt fp t+ ve
du >rd+p+ty

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