Physics 11
Unit III Practice Test
Projectile Motion
Instructions: Pick the best answer available in Part A and Show all your work for Part B
1.
Which of the following is constant for all projectiles?
A. Vertical velocity
B. Horizontal velocity *
C. Vertical displacement
D. Horizontal displacement
2.
Consider three points in the path of a certain projectile as shown in the diagram below. What is the
acceleration of the projectile at each of these points? D
3.
The projectile shown below has an acceleration which is:
A. Zero.
B. In the direction of P.
C. In the direction of Q.
D. In the direction of R. *
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4.
Which of the following remain(s) constant for a projectile: its horizontal velocity component, v H , its
vertical velocity component, vV , its vertical acceleration, g?
A. vV
B. g and vV
C. g and v H *
D. g, v H and vV
5.
Which of the following graphs represents the horizontal velocity component (v x ) versus time for a
projectile thrown horizontally off a cliff? (Ignore air resistance.) A
6.
What is the range of the projectile launched horizontally at 25 m/s from the 18 m-high cliff edge as
shown in the diagram below?
A. 18 m
B. 30 m
C. 46 m
D. 48 m *
2
7.
A projectile is launched over level ground with an initial velocity of 65 m/s at 30° above the
horizontal. What is the projectile’s time of flight?
A. 3.6 s
B. 6.6 s *
C. 11 s
D. 13 s
8.
A projectile is launched at 30 m/s over level ground at an angle of 37° to the horizontal. What
maximum height does this projectile reach?
A. 3.1 m
B. 17 m *
C. 29 m
D. 46 m
9.
A blue marble rolls off of the end of a table at 2.5 m/s. The tabletop is 1.5 m above the floor. How
much time passes before the marble hits the floor?
A. 0.35 s
B. 0.55 s *
C. 0.60 s
D. 1.2 s
10.
A projectile is launched with a velocity of 35 m/s at 55° above the horizontal. What is the maximum
height reached by the projectile? Ignore friction.
A. 5.3 m
B. 42 m *
C. 54 m
D. 63 m
11.
An astronaut on the moon throws a 5.0 kg wrench vertically upwards with an initial speed of 15
m/s. The acceleration due to gravity on the surface of the moon is one-sixth that on the surface of
the earth. What is the maximum height reached by the wrench?
A. 25 m
B. 46 m
C. 69 m *
D. 75 m
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12.
A ball rolls off a horizontal roof at 15 m/s. How far will the ball have fallen vertically when it
reaches a speed of 24 m/s?
A. 4.1 m
B. 18 m *
C. 29 m
D. 37 m
13.
A brick is thrown horizontally with an initial speed of 41 m/s from a cliff 32.0 m above a lake. If
air resistance is negligible, what is the velocity of the brick at the moment of its impact with the
water?
A.
B.
C.
D.
14.
A cannonball is fired with an initial velocity of 120 m/s at an angle of 30° above the horizontal. If
air resistance is negligible, how much time elapses before the cannonball strikes the ground at the
same elevation from which it was fired?
A.
B.
C.
D.
15.
28 m/s @ 30° from the horizontal
38 m/s @ 60° from the horizontal
48 m/s @ 30° from the horizontal * angle has been rounded
18 m/s @ 60° from the horizontal
42 s
31 s
24 s
12 s *
An object is launched at 65° to the horizontal with an initial speed of 25 m/s. What is the maximum
height reached by this object?
A. 5.7 m
B. 26 m *
C. 32 m
D. 150 m
16.
When a 2.0 kg red rock is dropped from a cliff it hits the beach at 24 m/s. At what speed would a
4.0 kg rock, dropped from the same cliff, hit the beach? Ignore friction.
A. 12 m/s
B. 24 m/s *
C. 34 m/s
D. 48 m/s
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17.
A ball is thrown from level ground at 24 m/s, 30° above horizontal. How much time will it take to
reach its maximum height?
A. 1.2 s *
B. 2.1 s
C. 2.4 s
D. 7.3 s
18.
At t = 0 s a ball rolls off the edge of a vertical cliff. At t = 2.0 s the ball is 6.0 m from the cliff as
shown. How far is the ball from the cliff at t = 4.0 s?
A. 6.0 m
B. 9.0 m
C. 12 m *
D. 24 m
19.
A projectile is launched over level ground at 35 m/s at an angle of 40° above the horizontal. What is
the projectile’s time of flight?
A. 2.3 s
B. 4.6 s *
C. 5.5 s
D. 7.1 s
1. A soccer ball is kicked over level ground with an initial velocity of 18 m/s, 24° above the horizontal.
a) How long does it take the ball to return to the ground? 1.5 seconds
b) What is the range of the ball? 25 m
2.
A projectile is launched over level ground at 85 m/s, 25° above the horizontal. Air resistance may be
ignored.
a) Calculate the range (horizontal distance) of the projectile.
560 or 570 m depending on your rounding
b) Using principles of physics, comment on the horizontal and vertical components of the
projectile’s velocity and acceleration during the flight.
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3.
Mike runs horizontally off a cliff at 6.5 m/s and lands in the water 15 m from the base of the cliff.
a) How long does it take Mike to hit the water? 2.3 seconds
b) How high is the cliff? 26 m
4.
The first colonists on Mars conduct a physics experiment by dropping a small mass (from rest) and
recording its displacement at regular time intervals. This data is shown below.
a) Plot a graph of displacement versus time squared and draw the best-fit straight line.
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b) Determine the slope of the line.
c) Based on this experiment, what is the acceleration due to gravity on Mars?
5.
The data table shows the velocity of a car during a 5.0 s interval.
0.0 1.0 2.0 3.0 4.0 5.0
Time (s)
Velocity (m/s) 13 16 16 19 21 22
a) Plot the data and draw a best-fit straight line.
b) Calculate the area bounded by the graph and the time axis between t = 0.0 s and t = 5.0 s.
Case III
6.
A rock is thrown from a cliff top at 18 m/s, 25° above the horizontal. It lands on the beach 4.2 s later.
a) What is the height h of the cliff? 54 m
b) How far from the base of the cliff d did the rock land? 69 m
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