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Physics
Chapter 6 Examination
For this examination, you may use your book, notes, the Internets and other
resources but you may not use other individuals. Be sure to answer each
question fully and completely using nouns, verbs and –ly words to document
your path to solution.
1. Explain how your Physics DAY project relates to Chapter 6.
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 2. The path of a projectile through space is called its:
a. equilibrant
c. range
b. torque
d. trajectory
____ 3. A soldier throws a grenade horizontally from the top of a cliff. Which of the
following curves best describes the path taken by the grenade?
a. Circle
c. Hyperbola
b. Ellipse
d. Parabola
____ 4. A stone is thrown horizontally from the top of a 25.00-m cliff. The stone
lands at a distance of 40.00 m from the edge of the cliff. What is the initial
horizontal velocity of the stone?
a. 2.260 m/s
c. 17.70 m/s
b. 15.60 m/s
d. 22.05 m/s
____ 5. A ball is thrown horizontally at 10.0 m/s from the top of a hill 50.0 m high.
How far from the base of the cliff would the ball hit the ground?
a. 23.6 m
c. 31.9 m
b. 26.4 m
d. 45.0 m
David A. Young
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06/28/2017
Physics
Chapter 6 Examination
____ 6. A ball is thrown horizontally from a hill 29.0 m high at a velocity of 4.00
m/s. Find the distance between the base of the hill and the point where the
ball hits the ground.
a. 2.43 m
c. 10.06 m
b. 9.73 m
d. 3.28 m
____ 7. A player kicks a football at an angle of 30.0° above the horizontal. The
football has an initial velocity of 20.0 m/s. Find the horizontal component of
the velocity and the maximum height attained by the football.
a. 10.0 m/s, 17.6 m
c. 25.1 m/s, 7.40 m
b. 17.3 m/s, 5.10 m
d. 30.3 m/s, 9.50 m
____ 8. A missile launches at a velocity of 30.0 m/s at an angle of 30.0° to the
normal. What is the maximum height the missile attains?
a. 11.5 m
c. 34.4 m
b. 27.5 m
d. 45.9 m
____ 9. A player kicks a football with an initial velocity of 3.00 m/s at an angle of
60.0° above the horizontal. What is the horizontal distance traveled by the
football?
a. 0.312 m
c. 0.673 m
b. 0.397 m
d. 0.795 m
____10. The movement of an object or a point mass at a constant speed around a
circle that has a fixed radius is called uniform:
a. circular motion
c. elliptical motion
b. parabolic motion
d. rotational motion
____11. A sprinter runs at a speed of 3.00 m/s on a circular track that has a radius of
40.00 m. Find the centripetal acceleration of the sprinter.
a. 0.225 m/s2
c. 0.750 m/s2
b. 4.44 m/s2
d. 0.0750 m/s2
David A. Young
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06/28/2017
Physics
Chapter 6 Examination
____12. A 0.50-kg ball is attached to a string of 0.50 m and swung in a horizontal
circle with a velocity of 1.0 m/s. Find the centripetal force of the ball.
a. 0.50 N
c. 2.0 N
b. 1.0 N
d. 2.5 N
____13. A 1.00-kg ball is attached to a string of 0.50 m and swung in a horizontal
circle with a velocity of 2.00 m/s. Find the centripetal acceleration.
a. 0.25 m/s2
c. 4.0 m/s2
b. 2.0 m/s2
d. 8.0 m/s2
The diagram below shows the trajectories of two balls. The magnitude of the
initial velocity is vi, the launch angle is , and the horizontal and vertical
components of the initial velocity are vxi and vyi.
____14. Compare the values of i. The value for ball A
a. is greater than the value for ball B.
b. is equal to the value for ball B.
c. is less than the value for ball B.
d. cannot be compared with the value for ball B using only the
information given.
David A. Young
page 3
06/28/2017
Physics
Chapter 6 Examination
____15. Compare the values of vi. The value for ball A
a. is greater than the value for ball B.
b. is equal to the value for ball B.
c. is less than the value for ball B.
d. cannot be compared with the value for ball B using only the
information given.
____16. Compare the values of vxi. The value for ball A
a. is greater than the value for ball B.
b. is equal to the value for ball B.
c. is less than the value for ball B.
d. cannot be compared with the value for ball B using only the
information given.
____17. Compare the values of vyi. The value for ball A
a. is greater than the value for ball B.
b. is equal to the value for ball B.
c. is less than the value for ball B.
d. cannot be compared with the value for ball B using only the
information given.
____18. Two balls are thrown horizontally. Ball C is thrown with a force of 20 N,
and ball D is thrown with a force of 40 N. Assuming all other factors are
equal, ball D will fall toward the ground
a. faster than ball C.
b. more slowly than ball C.
c. at the same rate as ball C.
d. at a rate that cannot be compared with that of ball C using the
information given.
David A. Young
page 4
06/28/2017
Physics
Chapter 6 Examination
Short Answer
19. An object in uniform circular motion moves at a constant speed around a
circle with a fixed radius. Why is the object said to be accelerating though it
has a constant speed?
Problem
20. A hiker throws a ball at an angle of 21.0° above the horizontal from a hill
21.0 m high. The hiker’s height is 1.750 m. The magnitudes of the horizontal
and vertical components of the velocity are 14.004 m/s and 5.376 m/s,
respectively. Find the distance between the base of the hill and the point
where the ball hits the ground. (Consider the hiker’s height while calculating
the answer.)
21. Two grenades, A and B, are thrown horizontally with different speeds from
the top of a cliff 70 m high. The speed of A is 2.50 m/s and the speed of B is
3.40 m/s. Both grenades remain in air for 3.77 s. Assume that the
acceleration due to gravity is 9.86 m/s2. What is the distance between A and
B if they are thrown along the same straight line?
22. A boat traveling east covers a distance of 40.0 m in 20.0 s. It encounters a
current moving at a speed of 2.50 m/s traveling north. Find the resultant
velocity of the boat.
23. A riverboat travels with a velocity of 4.60 m/s from one shore to another.
The velocity of the river is 2.30 m/s. If the width of the river is 72.0 m, how
far does the boat travel downstream to reach the other shore?
24. A bus travels from west to east with a velocity of 11.5 m/s. A marble rolls
on the surface of the bus floor with a velocity of 0.200 m/s north. What is
the velocity of the marble relative to the road?
25. A pilot wants to fly due north a distance of 125 km. The wind is blowing out
of the west at a constant 35 km/h. If the plane can travel at 175 km/h, how
long will the trip take?
David A. Young
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06/28/2017
Physics
Chapter 6 Examination
26. A boy ties a 58-g tennis ball to the end of a light string that is 65 cm long
and whirls the ball above his head in a horizontal circle, as shown at right.
The boy exerts a force of 5.2 N on the string to keep the ball moving in a
circle at a height of 1.7 m above the ground.
a.
Determine the speed of the ball.
b.
Suppose that the string breaks as the ball swings in its circular path.
Describe the motion of the ball
(i)
the instant after the string breaks.
(ii) after the string breaks but before it hits the ground.
c.
How long will it take the ball to reach the ground?
d.
How far will the ball travel horizontally before it hits the ground?
27. Simulate question 20 on the TI Nspire. Report the Big 3: Range, Hang Time,
and Maximum Height.
28. Simulate question 20 in the Projectile Motion Simulator with the person
standing on the ground. Select the type of ball and assume air resistance. Report
the Big 3: Range, Hang Time, and Maximum Height.
29. Explain this image in the context of Chapter 6:
David A. Young
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06/28/2017