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Homework Booklet
National 5 Physics
Dynamics and Space Part 1
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Practice questions on Speed, Velocity and
Displacement
(From HSDU Int2 Pupil Materials Pack)
1.
A runner completes a 200 m race in 25 s. What is his average speed in m/s? What is his
average speed in ms-1?
2.
A friend asks you to measure his average cycling speed along flat road. Describe which
measurements you would take and the measuring instruments you would use.
3.
An athlete takes 4 minutes 20 s to complete a 1500 m race. What is the average speed?
4.
On a fun run, a competitor runs 10 km in 1 hour.
What is her average speed in:
a)
kmh-1 b)
ms-1?
5.
Describe how you could measure the average speed of a car as it passes along the road
outside your school/college.
6.
Concorde can travel at 680 ms-1 (twice the speed of sound).
How far will it travel in 25 s at this speed?
7.
A girl can walk at an average speed of 2 ms-1. How far will she walk in 20 minutes?
8.
How long will it take a cyclist to travel 40 km at an average speed of 5 ms-1?
9.
How long (to the nearest minute) will the Glasgow to London shuttle take if it flies at an
average speed of 220 ms-1 for the 750 km flight?
10. How long, to the nearest minute, will a car take to travel 50 km if its average speed is 20 ms-1?
11.
Look at this timetable for a train between Edinburgh and Glasgow:
a)
b)
c)
Station
Time
Glasgow
Falkirk
Linlithgow
Edinburgh
0800
0820
0828
0850
Distance from
Glasgow
0 km
34km
46 km
73 km
What was the average speed for the whole journey in ms-1?
What was the average speed in m/s between Glasgow and Falkirk?
Explain the difference in average speeds in a) and b).
12. Describe how you would measure the instantaneous speed of a vehicle as it reached the
bottom of a slope.
13. In an experiment to measure instantaneous speed, these measurements were obtained:Reading on timer =
0.125 s
Length of car
=
5 cm
Calculate the instantaneous speed of the vehicle in ms-1.
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14. A trolley with a 10 cm card attached to it is released from A and runs down the
slope, passing through a light gate at B, and stopping at C.
Time from A to B = 0.8 s.
Time on light gate timer = 0.067 s
A
C
B
60cm
40cm
a) What is the average speed between A and B?
b) What is the instantaneous speed at B?
15. What is the difference between a vector quantity and a scalar quantity?
16. Use your answer to question 15 to explain the difference between distance and
displacement.
17. A man walks from X to Y along a winding road.
a) What is his displacement at the end of his walk?
b) What distance has he walked?
18. If the walker in question 17 took 40 minutes for his walk, what was:
a) his average speed
b) his average velocity?
19. One complete lap of a running track is 400m.
An athlete completes one lap in 48 s in the 400 m race. What is his:
a) distance travelled
b) displacement
c) average speed
d) average velocity
e) explain the difference between your answers to parts c and d above.
20.
Repeat Q 19 for a runner in the 800 m race whose winning time was 1 min 54 s.
21. A car travels 40 km north, then turns back south for 10 km.
The journey takes 1 hour.
What is:
a) the displacement of the car
b) the distance the car has travelled
c) the average velocity of the car i n km h-1?
d) the average speed of the car in km h-1 ?
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22. A car drives 60 km north, then 80 km east, as shown in the diagram. The journey takes 2 hours.
Calculate the
a) distance travelled
b) displacement
c) average speed
d) average velocity.
Practice questions on Velocity time graphs
(From HSDU Int2 Pupil Materials Pack)
23. The graph below shows how the velocity of a car varies over a 40s period.
a)
b)
c)
d)
e)
24.
Describe the motion of the car during this 40 s period.
Calculate the acceleration of the vehicle.
How far does the car travel while accelerating?
What is the total distance travelled by the car?
What is the final displacement of the car?
Use the graph below to answer the following questions.
10
a) During which time is the vehicle travelling at a constant velocity?
b) Calculate the values of
i) the initial acceleration ii) the final deceleration
c) What is the braking distance of the car?
d) What is the total distance travelled?
e) What is the average velocity of the car?
25.
Draw a velocity-time graph to describe the following motion:A car accelerates from rest at 2 ms-1 for 8 s, then travels at a constant velocity for 12 s, finally
slowing steadily to a halt in 4 s.
26.
For the vehicle in the previous question, what are the values of
a) the maximum velocity
b) the distance travelled
c) the average velocity?
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27.
The graph below describes the motion of a cyclist.
a) What is the value of the maximum positive acceleration?
b) Show by calculation whether the cyclist travels farther while accelerating, or while cycling at the
maximum velocity.
Practice questions on Acceleration
(From HSDU Int2 Pupil Materials Pack)
28. A Jaguar can reach 27 ms-1 from rest in 9.0 s. What is its acceleration?
29. The space shuttle reaches 1000 ms-1, 45 s after launch.
What is its acceleration?
30. A car reach 30 ms-1 from a speed of 18 ms-1 in 6 s. What is its acceleration?
31. A train moving at 10 ms-1 increases its speed to 45 m/s in 10 s. What is its
acceleration?
32. A bullet travelling at 240 ms-1 hits a wall and stops in 0.2 s.
What is its acceleration?
33. A car travelling at 20 ms-1 brakes and slows to a halt in 8 s.
What is the deceleration?
34. Describe how you would measure the acceleration of a small vehicle as it runs down a slope
in the laboratory.
35. On approaching the speed limit signs, a car slows from 30 ms-1 to 12 ms-1 in
5 s. What is its deceleration?
36. A bowling ball is accelerated from rest at 3 ms-2 for 1.2 s. What final speed will it reach?
37. How long will it take a car to increase its speed from 8 ms-1 to 20 ms-1 if it accelerates at 3
ms-2?
38. A cyclist can accelerate at 0.5 m/s2 when cycling at 4 ms-1. How long will she take to reach
5.5 ms-1?
39. The maximum deceleration a car’s brakes can safely produce is 8 ms-2. What will be the
minimum stopping time if the driver applies the brakes when travelling at 60 mph (27 ms-1).
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40. The table below gives some performance figures for cars.
Car
Mondeo 1.8 LX
Peugeot 106 XN
1.1
Renalt Clio RL
Nissan Micra 1.0 S
Porsche Boxster
a)
b)
c)
d)
Time for 0 - 60 mph
10.2 s
12.5 s
14.3 s
15.2 s
6.5 s
max. speed in mph
122
103
95
89
139
What is meant by the term acceleration?
Which car has the smallest acceleration?
Which car has the largest acceleration?
Assuming that the acceleration remained constant, how long would it take for the
following cars to reach their top speed?
i) Mondeo
ii)Porsche
Practice questions on Forces, Motion and
Newton’s Laws
(From HSDU Int2 Pupil Materials Pack)
41. What is meant by the resultant force on an object?
42. What are the resultants of the following forces?
a)
Engine force
c)
b)
Friction
Air resistance
Weight
Thrust
Thrust
43. By using a scale diagram or otherwise, find the resultant of the following pairs of forces.
44. What force is needed to accelerate a 5 kg mass at 3 ms-2 ?
45. What will be the acceleration of a 12 kg mass acted on by a force of 30 N?
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46. What mass would accelerate at 2 ms-2 when acted on by a 12 N force?
47. What force will accelerate 250 g at 2 ms-2 ?
48. What force would be needed to accelerate a 10 tonne lorry at 1.5 ms-2?
(1 tonne = 1000 kg)
49. A car travels at 60mph along a motorway
a)
How can the friction experienced by the car be reduced?
b)
How does the friction experienced by the car compare when it increases its speed to
70mph?
c)
How are the acceleration and the top speed of the car affected if a roof rack is added
to the car?
d)
What happens to the speed of the car if the car’s engine suddenly turns off?
Why does this happen?
e) Give two reasons why a car will have a smaller acceleration in similar conditions when a
roof rack is added.
50. Describe an experiment to investigate the effect of varying the unbalanced force acting on a
fixed mass.
51. A car of mass 1200 kg experiences friction equal to 500 N when travelling at a certain
speed. If the engine force is 1400 N, what will be the car’s acceleration?
52. A car of mass 2000 kg has a total engine force of 4500 N. The frictional drag force acting
against the car is 1700 N. What is the acceleration of the car?
53. Two girls push a car of mass 1000 kg. Each pushes with a force of 100 N and the force of
friction is 120 N. Calculate the acceleration of the car.
54. A boat engine produces a force of 10000 N and the friction and water resistance total
3500 N. If the mass of the boat is 2000 kg, what will be its acceleration?
55. A careless driver tries to start his car with the hand brake still on. The engine exerts a force
of 2500 N and the hand brake exerts a force of 1300 N. The car moves off with an
acceleration of 1.2 ms-2. What is the mass of the car?
56. A car of mass 1200 kg can accelerate at 2 ms-2 with an engine force of 3000 N.
What must be the total friction force acting on the car?
57. A helicopter winches an injured climber up from a mountainside.
The climber’s mass is 65 kg.
a) What is the weight of the climber?
b) If he is accelerated upwards at 1.0 ms-2, what unbalanced force is required?
c) What total upwards force must be produced by the helicopter?
58. An 800 kg car is accelerated from 0 to 18 ms-1 in 12 seconds.
a) What is the resultant force acting on the car?
b) At the end of the 12 s period the brakes are operated and the car comes to rest in a
time of 5 s. What is the average braking force acting on the car?
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Open Ended Questions for Dynamics
59. Two ice hockey players collide side on as they aim for the puck.
Using your knowledge of physics, comment on the motion of the ice hockey players after the collision.
60. A velocity-time graph of skydiver 1 is shown below.
Vel
oci
ty
(m
40
-1
s )
5
70
0
time (s)
A velocity-time graph of skydiver 2 is shown below
velo 50
city
(ms
1
)
2
0
90
time (s)
Use your knowledge of physics to explain how the second skydiver’s velocity-time graph during descent
compares with that of the first skydiver.
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61. Large ships are often helped into port by using two tug boats – one either side of the ship.
April 5, 1989 (Anchorage Daily News / Erik Hill)
Using your knowledge of physics, comment on the challenges faced by the two tug-boats to ensure that the ship
is docked safely.
62. A runner runs a marathon distance, starting from his own house. He finishes the 26∙1 mile run but is only 1
mile from his house.
Using your knowledge of physics, comment on why this is possible.
63. Bloodhound is a new design project with the intension to build a car that can drive at over 1000mph.
Use your knowledge of physics to describe some of the challenges that may face the design team in their quest
to break the world record.
64. The acceleration of a trolley running down a slope can be measured in two ways.
1 – single mask and two light gates connected to a computer set to calculate acceleration
2 – double mask and single light gate connected to a computer set to calculate acceleration
mask
mask
light
gate
light
gate
The light gates and masks are used to calculate two different velocities of the trolley. These velocities are then
used to calculate the acceleration of the trolley.
Using your knowledge of physics, comment on the reliability of the two methods used to calculate the
acceleration of the trolley down the slope.
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National 5 Section 1 Exam Style Questions for
Unit 3A Dynamics
65. (Qn 1 Int 2 Physics 2007)
67. (Qn 1 Int 2 Physics 2008)
68. (Qn 2 Int 2 Physics 2008)
66. (Qn 2 Int 2 Physics 2007)
69. (Qn 3 Int 2 Physics 2008)
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70. (Qn 4 Int 2 Physics 2008)
73. (Qn 3 Int 2 Physics 2009)
71. (Qn 1 Int 2 Physics 2009)
74. (Qn 5 Int 2 Physics 2009)
72. (Qn 2 Int 2 Physics 2009)
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75. (Qn 1 Int 2 Physics 2010)
78. (Qn 3 Int 2 Physics 2010)
76. (Qn 2 Int 2 Physics 2010)
79. (Qn 2 Int 2 Physics 2011)
77. (Qn 1 Int 2 Physics 2011)
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80. (Qn 1 Int 2 Physics 2012)
82. (Qn 3 Int 2 Physics 2012)
83. (Qn 4 Int 2 Physics 2012)
81. (Qn 2 Int 2 Physics 2012)
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National 5 Section 2 Exam Style Questions for
Unit 3A Dynamics
84. (Qn 10 Credit Physics 2007)
(c) (Jearl Walker qn 4.30)
Some cars are fitted with extra deep bumpers which reduce the air gap between the bottom of the car and the
road. Use your understanding of Physics to explain what effect, if any, this would have on the time taken for the
car to complete this journey.
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85. (Qn 11 Credit Physics 2007)
(c)
(Haliday, Resnick and Walker eqn 2.16)
When the aeroplane takes off from the aircraft carrier it only has a length of 300m to accelerate from
rest to 400 ms-1. The required acceleration, in ms-2, can be calculated using the equation:
Where l is the length available for acceleration and v is the velocity needed for take-off.
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86. (Qn 22 Int2 Physics 2007)
(c)
(Jearl Walker qn 2.3)
The cyclist approaches a second set of traffic light at 8 m/s . As the cyclist approaches the light turns from green
to orange. The cyclist has to decide quickly weather to decelerate to a stop, continue on at a constant speed or
accelerate across the junction. What factors should the cyclist consider when making the decision?
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87. (Qn 11 Credit Physics 2008)
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88. (Qn 21 Int2 Physics 2008)
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89. (Qn 11 Credit Physics 2009)
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90. (Qn 22 Int2 Physics 2009)
(d) (Jearl Walker qn 2.5)
The following day the same child sledges down the same hill on the same sledge. Overnight a snow drift has
formed in the area between B and C.
Should the child pull the break on the sledge in an attempt to slow down before hitting the drift or steer to the
right to avoid the snow drift? Use your understanding of Physics to justify your choice.
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91. (Qn 10 Credit Physics 2010)
(c)
(Haliday, Resnick and Walker eqn 6.15)
The decelerating force experienced by the cyclist is provided as a result of friction. The frictional force
applied to the cycle, in Newton’s, can be calculated using the formula:
where µ is the coefficient of friction. Calculate the coefficient of friction experiences by the cyclist as
they come to a stop at the traffic lights. Units for the coefficient of friction are not required.
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92. (Qn 21 Int2 Physics 2010)
(d)
(Haliday, Resnick and Walker eqn 6.18)
During the balloons descent the maximum speed reached by the balloon can be calculated using the
formula:
where m is the mass of the descending balloon.
Calculate the maximum speed reached by the balloon as it descends.
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93. (Qn 9 Credit Physics 2011)
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94. (Qn 10 Credit Physics 2012)
(d)
(Haliday, Resnick and Walker eqn 6.17)
The drag force, in Newton’s, experienced by the cyclist can be calculated using the formula:
where v is the velocity of the cyclist.
Calculate the drag force experienced by the cyclist when they are travelling at a constant speed during
the race.
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Practice questions on Speed, Velocity and
Displacement (Answers)
(From HSDU Int2 Pupil Materials Pack)
1.
8 m/s
3.
4.
5.8 m/s
a) 10 km/h
b) 2.8 m/s
17000 m
2400 m
8000 s ( 2 h 13 min )
57 min
42 min
a) 24.3 m/s
b) 28.3 m/s
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Use a light gate attached to a timing device such as a TSA. When the vehicle enters the light
gate and breaks the beam the timer will be started. When the vehicle leaves the light gate
and the beam is detected the timer will be stopped. The length of vehicle should be
measured with a measuring tape. The speed of the vehicle can be calculated by dividing the
length of vehicle by the time shown on the timer/TSA.
0.4 ms-1
a) 0.75 ms-1
b) 1.5 ms-1
A scalar has only size but a vector has size and direction.
Distance is a scalar – it only has size but displacement is a vector it has size and direction.
a) 2 km west b) 3.6 km
a) 1.5 ms-1
b) 0.83 ms-1west
19. a) 400 m
e) The speed of the car is calculated from the total distance
b) 0 m
travelled and has only magnitude (size) whereas the
c) 8.3 ms-1
velocity is calculated from the displacement from start to
d) 0 ms-1
finish and has both magnitude (size) and direction)
20. a) 800 m
20. a)
b) 800
0mm
c) 7 ms-1
d) 0 ms-1
21. a) 30 km north
b) 50 km
c) 30 km/h north
d) 50 kmh-1
22. a) 140 km
b) 100 km at (053)
c) 70 kmh-1
d) 50 kmh-1 at (053)
3 m/s2
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23.
16.
17.
18.
Practice questions on Velocity time graphs
(From HSDU Int2 Pupil Materials Pack)
23
a) Accelerates at a steady rate between 0 and 10s then maintains a velocity until
40s
b) 1.5 ms-2
24
c) 75 m
e) 525m
d) 525 m
a) 30 - 90 s
b) i) 0.7 ms-2 ii) –2 ms-2
c) 225 m
d) 2625 m
e) 25 ms-1
25
Velocity /ms-1
2
Time/s
8
26
27
20
24
a) 16 ms-1
b) 288 m
c) 12 ms-1
a) 0.3 ms-2
b) accelerating 200 m, constant velocity 160 m
Practice questions on Acceleration
(From HSDU Int2 Pupil Materials Pack)
28.
3 m/s2
29.
30.
22.2 m/s2
2 m/s2
31.
3.5 m/s2
32.
1200 m/s2
33.
– 2.5 ms-2
34.
Use two light gates, each connected to a TSA. One placed at the top and the other at the
bottom of the slope. A ruler should be used measure the length of the mask placed on the
vehicle and this should be input to the TSA. A stop watch should be used to time how
long it takes the vehicles to travel between the light gates. Acceleration is calculated by
finding the difference between the velocities shown on the TSAs and dividing this by the
time measured on the stop watch.
35.
– 3.6 ms-2
36.
3.6 ms-1
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37.
4s
38.
3s
39.
3.4 s
40.
b) Micra
a) How much a objects velocity
changes in one second
c) Porsche
d) i) 20.7 s ii) 15.1s b) 1.5 ms-2
Practice questions on Forces, Motion and
Newton’s Laws
(From HSDU Int2 Pupil Materials Pack)
41
.42
.
43
.
44
.
45
.46
.47
.48
.49
50
51
.57
.
58
.
Unbalanced or overall force
a) 800 N to left
b) 100 N down
c) 100000 N to right
a) 13 N at (067)
b) 15.8 N at (198)
c) 30 N at (053)
d) 12.8 N at (309)
15 N
2.5 ms-2
6 kg
0.5 N
15000 N
a) Friction can be reducing by streamlining the car
b) Friction increases
c) Acceleration decreases because mass of car increases and unbalanced force
decreases due to increased frictional force. Top speed is reduced since the terminal
velocity is now lower due to increased friction.
d) The cars speed decreases due to the friction from the road and the air
Use a light gate connected to a TSA to determine the acceleration of a vehicle with a double
mask. The length of one section of the double mask should be measured with a ruler and
input to the TSA. Small masses should be attached to a string connected to the front of the
cart and allowed to fall in order to accelerate the cart. The force generated by the falling
masses should be measured with a Newton meter and altered by adding or removing
masses. A graph of number of the accelerating force should be plotted against the resulting
acceleration measured by the TSA.
0.75 ms-2 52. 1.4 ms-2 53. 0.08 ms-2 54. 3.25 ms-2 55. 1000 kg 56. 600 N
a) 650 N
b) 65 N
c) 715 N
a) 1200 N
b) 2880 N
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National 5 Section 1 Exam Style Questions for
Unit 3A Dynamics
65. E (Qn 1 Int 2 Physics 2007)
66. B (Qn 2 Int 2 Physics 2007)
67. E (Qn 1 Int 2 Physics 2008)
68. C (Qn 2 Int 2 Physics 2008)
69. C (Qn 3 Int 2 Physics 2008)
70. B (Qn 4 Int 2 Physics 2008)
72. C (Qn 2 Int 2 Physics 2009)
73. E (Qn 3 Int 2 Physics 2009)
74. B (Qn 5 Int 2 Physics 2009)
75. E (Qn 1 Int 2 Physics 2010)
76. D (Qn 2 Int 2 Physics 2010)
77. D (Qn 1 Int 2 Physics 2011)
78. B (Qn 3 Int 2 Physics 2010)
79. B (Qn 2 Int 2 Physics 2011)
80. D (Qn 1 Int 2 Physics 2012)
81. A (Qn 2 Int 2 Physics 2012)
82. D (Qn 3 Int 2 Physics 2012)
83. B (Qn 4 Int 2 Physics 2012)
71. C (Qn 1 Int 2 Physics 2009)
National 5 Section 2 Exam Style Questions for
Unit 3A Dynamics
84. (Qn 10 Credit Physics 2007)
a) ii)
a)
a) iii)
b)
b)
c)
c)
Arguments related to increase in time
go along the lines of area of contact with
air increased so air resistance increased
which reduces the acceleration and top
speed of the car.
86. (Qn 22 Int2 Physics 2007)
Arguments related to no change in time
go along the lines of small percentage
changes leading to very little overall
change on this journey.
85. (Qn 11 Credit Physics 2007)
a) i)
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89. (Qn 11 Credit Physics 2009)
90. (Qn 22 Int2 Physics 2009)
(c) Factors include those such as:
 time for which the light is orange and
distance across the junction in order to
work out is they can continue safely at a
constant speed or if they need to
accelerate
 breaking force that they can provide and
the decelerating force this would
generate based on the mass of the
cyclist and cycle

the friction from the road (weather and
tyre conditions) and the distance
needed to stop in before reaching the
light
(d)
Arguments for steering away so along the
lines of applying all force to change in
direction and not reducing speed allows the
child to be more likely to turn enough right
to avoid the drift entirely.
87. (Qn 11 Credit Physics 2008)
a) i)
Arguments for heading straight for the drift
go along the lines of applying all force to
breaking gives a better chance of stopping
before the drift or hitting it slowly since if
steering away part of the applied force is
used to slow the sledge down whilst the
other part of the force is used to change the
direction of the sledge.
91. (Qn 10 Credit Physics 2010)
a) i)
a) ii)
a) ii)
b)
b)
c)
88. (Qn 21 Int2 Physics 2008)
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92. (Qn 21 Int2 Physics 2010)
94. (Qn 2 Credit Physics 2012)
a)
b)
(d)
c) i)
93. (Qn 9 Credit Physics 2011)
a) i)
c) ii)
a) ii)
a) iii)
d)
65 N
b)
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