Download Unit 3Question Booklet Student

Part E
Tests + answers
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Unit
Area of study 1:
Motion in one and two
dimensions test
3
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Jacaranda Physics 2, 3rd Edition TSK
Part E — TESTS + ANSWERS
Total questions: 71
Total marks:
160
Digital doc:
Unit 3 Area of study 1:
Motion in one and two
dimensions
Formulae
● velocity; acceleration: v 
x
v
; a
t
t
● equations for constant acceleration:
v  u  at
1 2
at
2
v 2  u 2  2ax
x  ut 
1
x  (v  u )t
2
● Newton’s second law: Fma
● Hooke’s law: Fkx
● strain potential energy:
1 2
kx
2
● gravitational potential energy near the surface of the earth: mgh
● kinetic energy:
1 2
mv
2
● Newton’s law of universal gravitation: F  G
● gravitational field: g  G
M1 M 2
r2
M
r2
Prefixes/Units
nnano109
µmicro106
mmilli103
kkilo103
Mmega106
Ggiga109
1 tonne103 kg
Data
● universal gravitational constant6.71011 N m2 kg2
● In all questions the acceleration due to gravity is 10 m s2. Ignore the effect of air resistance unless otherwise directed.
Jacaranda Physics 2 TSK
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Test
Questions 1 to 3 refer to the following information:
A car is travelling at a speed of 25 m s1 when the driver sees a traffic hazard ahead. The driver takes 0.45 s to respond and
apply the brakes. The brakes and road conditions mean that the car decelerates at 8.0 m s2.
Question 1
How far does the car travel before the brakes are applied?
(2 marks)
Question 2
What is the total stopping distance of the car from when the driver notices the hazard?
(3 marks)
Question 3
What period of time elapsed from when the brakes were first applied to when the car stopped?
(2 marks)
Jacaranda Physics 2 TSK
154
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Test
(continued)
Questions 4 to 8 refer to the following information:
The graph below shows how velocity varies with time for a car travelling north along a road.
Question 4
What was the car’s instantaneous acceleration 25 seconds after starting?
(2 marks)
Question 5
For what period of time was the car travelling at a constant velocity?
(1 mark)
Question 6
What is the car’s final displacement from its starting point?
(2 marks)
Jacaranda Physics 2 TSK
155
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Test
(continued)
Question 7
What is the car’s average velocity for the trip?
(2 marks)
Question 8
Briefly describe the motion of the car as depicted in this graph.
(3 marks)
Questions 9 to 11 refer to the following information:
A cyclist is taking part in a race. The mass of the cyclist and bicycle is 75 kg. The cyclist, starting from rest, applies a constant
driving force and is travelling at a constant speed 16 metres from the start. The graph below shows the total resistance forces
applied to cyclist and bicycle over the first 20 metres of the race.
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Test
(continued)
Question 9
What is the magnitude of the net force acting on the cyclist and bicycle at a distance of 19 m from the start? Justify your
answer.
(2 marks)
Question 10
What is the magnitude of the constant driving force provided by the cyclist?
(2 marks)
Question 11
What is the magnitude of the acceleration of the cyclist and bicycle at a distance of 6 m from the start?
(3 marks)
Questions 12 to 16 refer to the following information:
A racing car of mass 750 kg travelling with a velocity of 40 m s1 west collides head-on with a solid wall. The car rebounds
with a velocity of 5.0 m s1 east. The car is in contact with the wall for 0.80 s. Assume that no external force acts on this
system.
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Test
(continued)
Question 12
What is the initial momentum of the car?
(2 marks)
Question 13
What is the change of momentum of the car while it is in contact with the wall?
(3 marks)
Question 14
What impulse is applied to the car?
(2 marks)
Question 15
Calculate the average force that the car exerts on the wall during the collision.
(3 marks)
Jacaranda Physics 2 TSK
158
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Test
(continued)
Question 16
State the law of conservation of momentum and account for any apparent loss of momentum in this collision.
(2 marks)
Questions 17 and 18 refer to the following information:
A crash test dummy of mass 15 kg is initially travelling at a speed of 20 m s1 before it is brought to rest by a force which
varies in a manner shown in the graph below.
Question 17
What is the initial momentum of the dummy?
(2 marks)
Question 18
What is the magnitude of the impulse on the dummy during the collision?
(3 marks)
Jacaranda Physics 2 TSK
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Test
(continued)
Question 19
What is the magnitude of the maximum force that acts on the dummy?
(2 marks)
Questions 20 to 22 refer to the following information:
A truck of mass 6.0103 kg is travelling west at a speed of 25 m s1 when it collides with a car of mass 1.2103 kg travelling
east at a speed of 20 m s1. The vehicles become locked together during the collision. The collision took 0.90 s.
Question 20
What is the velocity of the vehicles immediately after the collision? Assume that no external forces acted on the car and truck
during the collision.
(3 marks)
Question 21
Fully specify the change of momentum of the car.
(3 marks)
Jacaranda Physics 2 TSK
160
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Test
(continued)
Question 22
Fully specify the average force that the car exerts on the truck during the collision.
(2 marks)
Questions 23 and 24 refer to the following information:
The following diagram shows a car rolling down a slope. The car has a mass of 1.2103 kg and the slope is at 15 to the
horizontal. The acceleration due to gravity is 10 m s2.
Question 23
On the diagram mark in the forces acting on the car.
(3 marks)
Question 24
If the total resistance force acting on the car has a magnitude of 1000 N, calculate the acceleration of the car.
(3 marks)
Jacaranda Physics 2 TSK
161
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Questions 25 to 27 refer to the following information:
A spring is used to stop a model car of mass 24 kg after it rolls down a curved track. The graph below shows how force
applied by the spring changes as a function of compression. When the spring is compressed to its maximum by the model car,
it applies a stopping force of 800 N.
Question 25
How far is the spring compressed when the model car comes to a stop?
(1 mark)
Question 26
How much energy is stored in the spring at the instant that the model car stops?
(2 marks)
Jacaranda Physics 2 TSK
162
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 27
The model car rebounds from the spring. If 75% of the energy stored in the spring is returned to the model car, what is its
speed as it leaves the spring?
(2 marks)
Questions 28 to 30 refer to the following information:
A car of mass 1550 kg travelling with a speed of 12.0 m s1 collides head-on with a stationary car of mass 1220 kg. During the
collision the cars become locked together. Assume that no external forces act during the collision.
Question 28
What is the speed of the two cars after the collision?
(3 marks)
Question 29
Is this collision elastic? Use calculations to justify your answer.
(3 marks)
Jacaranda Physics 2 TSK
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Test
(continued)
Question 30
Account for any loss of kinetic energy that might have occurred.
(1 mark)
Questions 31 to 34 refer to the following information:
A student is carrying out an experiment to investigate projectile motion. She fires a metal ball horizontally from a bench top.
The bench top is 1.3 m above the floor and the ball hits the floor at a distance of 2.6 m from a point directly below the edge of
the bench. Assume that the floor is horizontal.
Question 31
What period of time elapses from when the ball leaves the bench to when it hits the floor?
(2 marks)
Question 32
At what speed did the ball leave the bench?
(2 marks)
Jacaranda Physics 2 TSK
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© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 33
What is the speed of the ball just before it strikes the floor?
(3 marks)
Question 34
What angle does the direction of travel of the ball make with the floor just before it hits the floor?
(2 marks)
Questions 35 to 39 refer to the following information:
During a stunt, a car is driven at high speed up a ramp. It leaves the ground with a speed of 26 m s1 at an angle of 28° to the
horizontal. For the following questions assume that the ground is horizontal.
Question 35
What is the horizontal component of the car’s initial velocity on leaving the ramp?
(2 marks)
Jacaranda Physics 2 TSK
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Test
(continued)
Question 36
What is the vertical component of the car’s initial velocity on leaving the ramp?
(2 marks)
Question 37
What horizontal distance does the car travel after leaving the ramp until it hits the ground?
(2 marks)
Question 38
What maximum additional height does the car gain after leaving the ramp?
(3 marks)
Question 39
How would the answers to the previous two questions be affected if the effect of air resistance was taken into account?
(2 marks)
Jacaranda Physics 2 TSK
166
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Questions 40 to 43 refer to the following information:
A car collides with a low brick wall and comes to rest.
A poorly secured parcel becomes detached from the roof of the car. It initially is travelling horizontally and it strikes the
ground a distance of 12 m from the point where it left the car. The parcel is initially 1.5 m above the ground. The situation is
shown in the diagram below.
Question 40
What period of time elapses before the parcel strikes the ground?
(2 marks)
Question 41
Estimate the speed of the car just before it collided with the wall.
(2 marks)
Question 42
What assumptions did you make in calculating the answer to the previous question?
(2 marks)
Jacaranda Physics 2 TSK
167
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 43
If air resistance is taken into account, which of the arrows AE in the diagram best give the direction of the net force acting on
the parcel at the instant shown?
(2 marks)
Questions 44 to 46 refer to the following information:
An object of mass 4.0 kg is moving with a constant speed in a horizontal circular path. The radius of the circle is 2.5 m. The
object completes 10 revolutions in 31.4 s.
Question 44
What is the speed of the object?
(2 marks)
Question 45
What is the magnitude of the net force acting on the object?
(2 marks)
Jacaranda Physics 2 TSK
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© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 46
What is the magnitude of the object’s acceleration?
(2 marks)
Questions 47 and 48 refer to the following information:
The diagram below shows an instantaneous overhead view of a student swinging a small object above her head using a piece
of cotton.
Question 47
Which of the arrows A to E best represents the direction of the net force acting on the object at the instant shown? Justify your
answer.
(2 marks)
Jacaranda Physics 2 TSK
169
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 48
If the piece of cotton broke at the instant shown, which of the arrows A to E best represents the direction that the object would
continue to travel in? Justify your answer.
(2 marks)
Questions 49 to 53 refer to the following information:
A car of mass 1200 kg is travelling at a constant speed of 15 m s1 around a bend that is an arc of a circle of radius 50 m. This
situation is shown in the diagram below. The surface of the road is banked at an angle of 15° to the horizontal to reduce the
reliance of any car on sideways function.
Question 49
What is the magnitude of the net force acting on the car?
(2 marks)
Jacaranda Physics 2 TSK
170
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 50
Which of the arrows AE gives the direction of the net force acting on the car at the instant shown?
(1 mark)
Question 51
A suitcase falls from the roof of the car at the instant shown.
Which of the arrows AE gives the direction that the suitcase will travel after losing contact with the car?
Justify your answer.
(3 marks)
Question 52
Describe the origin of the centripetal force that causes the car to follow a circular path.
(2 marks)
Question 53
With what maximum speed can the car travel around a bend without having to rely on sideways friction?
(2 marks)
Jacaranda Physics 2 TSK
171
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Questions 54 and 55 refer to the following information:
A skateboarder with a mass of 70 kg (including the mass of the skateboard) reaches point P at the bottom of a half-pipe at a
speed 8.0 m s–1. The middle section of the half-pipe forms the arc of a circle with a radius of 6.0 m.
Question 54
What is the magnitude of the centripetal force on the skateboarder at the point P?
(2 marks)
Question 55
Calculate the normal reaction force on the skateboarder at the point P.
(2 marks)
Questions 56 and 57 refer to the following information:
A car of mass 1200 kg travels over a speed hump at a speed of 6.0 m s–1. The speed hump forms the arc of a circle of radius
4.0 m.
Question 56
Determine the magnitude of the normal reaction of the car at the top of the speed hump.
(2 marks)
Jacaranda Physics 2 TSK
172
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 57
What is the minimum speed that the car would have to travel to momentarily lose contact with the ground at the top of the
speed hump?
(3 marks)
Questions 58 to 61 refer to the following information:
Saturn has at least 18 natural satellites, two of which are Titan and Tethys.
mass of Titan
radius of Titan
period of Titan’s orbit
radius of Titan’s orbit
mass of Tethys
radius of Tethys’ orbit
1.351023 kg
12.6106 m
1.38106 s
1.22109 m
17.41020 kg
12.9108 m
Question 58
Calculate the gravitational field strength of the surface of Titan.
(2 marks)
Question 59
What is the period of Tethy’s orbit?
(3 marks)
Jacaranda Physics 2 TSK
173
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 60
Use the data provided to calculate the mass of Saturn.
(3 marks)
Question 61
What is the orbital speed of Titan around Saturn?
(3 marks)
Questions 62 to 64 refer to the following information:
The space shuttle is in a circular orbit around the Earth at an altitude of 600 km above the Earth’s surface.
DATA: radius of the Earth6.4106 m
mass of the Earth6.01024 kg
Question 62
What is the radius of the shuttle’s orbit?
(1 mark)
Question 63
What is the force of gravity acting on a 75 kg occupant of the shuttle at this altitude?
(2 marks)
Jacaranda Physics 2 TSK
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© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Question 64
The travellers in an orbiting space shuttle experience apparent weightlessness. Explain why this occurs.
(3 marks)
Question 65
Are astronauts orbiting Earth really weightless? Explain your answer.
(2 marks)
Question 66
The graph below shows how the gravitational field strength (g) varies with distance from the centre of the Moon. An artificial
satellite of mass 250 kg orbits the Moon at a distance of 1.5106 m.
What is the change in the satellite’s potential energy if it is moved to a new orbit with a radius of 2.5106 m?
(3 marks)
Jacaranda Physics 2 TSK
175
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Questions 67 to 69 refer to the following information:
A satellite of mass ms is in elliptical orbit about a planet of mass Mp. The satellite is a distance of x kilometres from the centre
of the planet when it is closest (point A) and it is a distance of 2x kilometres from the centre of the planet when it is furthest
(point B). This situation is represented in the diagram below.
Question 67
What is the value of the ratio:
speed of the satellite at point A
?
speed of the satellite at point B
(3 marks)
Question 68
What is the value of the ratio:
magnitude of the acceleration of the satellite at point A
?
magnitude of the acceleration of the satellite at point B
(3 marks)
Question 69
What is the value of the ratio:
total energy of the satellite at point A
?
total energy of the satellite at point B
(3 marks)
Jacaranda Physics 2 TSK
176
© John Wiley & Sons Australia, Ltd 2009
Test
(continued)
Questions 70 and 71 refer to the following information:
The following graph shows the gravitational field strength as a function of the distance from the centre of the Earth. The
radius of the Earth is 6.4106 m.
Question 70
Estimate the amount of work required to lift a 50 kg mass from the surface of the Earth to a height of 2.6106 m above the
Earth’s surface.
(3 marks)
Question 71
Is the energy required to place a satellite of mass 50 kg into orbit at a height of 2.6106 m above the Earth’s surface:
A. less than
B. the same as
C. greater than
the answer to the previous question?
Explain your choice.
(3 marks)
Jacaranda Physics 2 TSK
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© John Wiley & Sons Australia, Ltd 2009