Question 1

A boy kicks a football from ground level with an initial velocity of 20 m/s at an angle of 30° above the horizontal.What is the horizontal distance to the point where the football hits the ground if we neglect air resistance?

Accepted Answer

A)  20 m
B)  35 m
C)  18 m
D)  60 m
E)  30.0 mF) A) and C)
G) All of the above

Question 2

A projectile is fired from the edge of a cliff as shown in the figure.The initial velocity components are 940 m/s (horizontal) and 96 m/s (vertical) .The projectile reaches maximum height at point P and then falls and strikes the ground at point Q.How high is point P above point Q,assuming no air resistance?

Accepted Answer

A)  470 m
B)  490 m
C)  45,000 m
D)  940 m
E)  90,000 mF) A) and B)
G) A) and C)

Question 3

A hockey puck slides off the edge of a horizontal platform with an initial velocity of 28.0 m/s horizontally in a city where the acceleration due to gravity is 9.81 m/s2.The puck experiences no significant air resistance as it falls.The height of the platform above the ground is 2.00 m.What is the angle below the horizontal of the velocity of the puck just before it hits the ground?

Accepted Answer

A)  77.2°
B)  72.6°
C)  12.8°
D)  12.6°
E)  31.8°F) A) and D)
G) B) and D)

Question 4

A hockey puck slides off the edge of a platform with an initial velocity of 20 m/s horizontally.The height of the platform above the ground is 2.0 m.What is the magnitude of the velocity of the puck just before it touches the ground? You can neglect air resistance.

Accepted Answer

A)  21 m/s
B)  22 m/s
C)  24 m/s
D)  25 m/s
E)  6.3 m/sF) A) and E)
G) A) and D)

Question 5

In an air-free chamber,a pebble is thrown horizontally,and at the same instant a second pebble is dropped from the same height.Compare the times of fall of the two pebbles.

Accepted Answer

A)  The thrown pebble hits first.
B)  The dropped pebble hits first.
C)  They hit at the same time.
D)  We cannot tell without knowing which pebble is heavier.E) C) and D)
F) None of the above

Question 6

The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively.If there is no air resistance,how long does it take the football to reach the top of its trajectory?

Accepted Answer

A)  1.0 s
B)  2.0 s
C)  3.0 s
D)  4.0 s
E)  5.0 sF) A) and E)
G) D) and E)

Question 7

A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically.Which object is traveling faster when it hits the level ground below if neither of them experiences any air resistance?

Accepted Answer

A)  It is impossible to tell because we do not know their masses.
B)  the stone
C)  the ball
D)  Both are traveling at the same speed.E) C) and D)
F) B) and D)

Question 8

A hobbyist launches a projectile from ground level on a horizontal plain.It reaches a maximum height of 72.3 m and lands 111 m from the launch point,with no appreciable air resistance.What was the angle of launch if g = 9.80 m/s2?

Accepted Answer

A)  69.0°
B)  67.4°
C)  22.6°
D)  44.8°E) B) and C)
F) None of the above

Question 9

A ball is thrown at an original speed of 8.0 m/s at an angle of 35° above the horizontal.If there is no air resistance,what is the speed of the ball when it returns to the same horizontal level?

Accepted Answer

A)  4.0 m/s
B)  8.0 m/s
C)  16 m/s
D)  9.8 m/sE) A) and B)
F) A) and C)

Question 10

An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 55° with the vertical.What is the length of the athlete's jump if air resistance is of no significance?

Accepted Answer

A)  0.88 m
B)  8.0 m
C)  12 m
D)  17 m
E)  4.0 mF) A) and E)
G) A) and D)

Question 11

A projectile is fired at an angle above the horizontal at a location where g = 9.8 m/s2.The initial x and y components of its velocity are 86.6 m/s and 50 m/s respectively.At what angle was the projectile fired above the horizontal?

Accepted Answer

A)  45°
B)  60°
C)  30°
D)  90°
E)  75°F) C) and E)
G) A) and C)

Question 12

Mary and Debra stand on a snow-covered roof.They both throw snowballs with the same initial speed,but in different directions.Mary throws her snowball downward,at 30° below the horizontal;Debra throws her snowball upward,at 30° above the horizontal.Which of the following statements are true about just as the snowballs reach the ground below? (There could be more than one correct choice. )

Accepted Answer

A)  Debra's snowball will have a higher speed than Mary's snowball.
B)  Mary's snowball will have a higher speed than Debra's snowball.
C)  Both snowballs will hit the ground with the same speed.
D)  Both snowballs hit the ground at the same time.
E)  Mary's snowball reaches the ground before Debra's snowball.F) B) and D)
G) A) and E)

Question 13

An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 35° above the horizontal.How long does the athlete stay in the air,assuming no significant air resistance?

Accepted Answer

A)  0.50 s
B)  0.88 s
C)  1.1 s
D)  2.5 s
E)  0.54 sF) A) and E)
G) B) and C)

Question 14

A pilot drops a package from a plane flying horizontally at a constant speed.Neglecting air resistance,when the package hits the ground the horizontal location of the plane will

Accepted Answer

A)  be behind the package.
B)  be directly over the package.
C)  be in front of the package.
D)  depend on the speed of the plane when the package was released.E) None of the above
F) A) and B)

Question 15

A wind farm generator uses a two-bladed propeller mounted on a pylon at a height of 20 m,as shown in the figure.The width of the pylon is very narrow,and the length of each propeller blade is 12 m.A tip of the propeller breaks off just when the propeller is vertical.The fragment flies off horizontally,falls,and strikes the ground at point P with negligible air resistance.Just before the fragment broke off,the propeller was turning uniformly,taking 1.2 s for each rotation.How far is point P from the base of the pylon?

Accepted Answer

A)  120 m
B)  130 m
C)  140 m
D)  150 m
E)  160 mF) All of the above
G) B) and D)

Question 16

A player kicks a soccer ball in a high arc toward the opponent's goal.At the highest point in its trajectory

Accepted Answer

A)  both the velocity and the acceleration of the soccer ball are zero.
B)  neither the ball's velocity nor its acceleration are zero.
C)  the ball's acceleration is zero but its velocity is not zero.
D)  the ball's acceleration points upward.
E)  the ball's velocity points downward.F) B) and E)
G) A) and B)

Question 17

A projectile is fired from ground level with a speed of 150 m/s at an angle 30° above the horizontal on an airless planet where g = 10.0 m/s2.What is the horizontal component of its velocity after 4.0 s?

Accepted Answer

A)  150 m/s
B)  35 m/s
C)  130 m/s
D)  75 m/s
E)  38 m/sF) A) and E)
G) A) and D)

Question 18

A boulder rolls off of a very high cliff and experiences no significant air resistance.While it is falling,its trajectory is never truly vertical.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice. )

Accepted Answer

A)  The speed of the object is constant but its velocity is not constant.
B)  The acceleration of the object is +g when the object is rising and -g when it is falling.
C)  The acceleration of the object is zero at its highest point.
D)  The speed of the object is zero at its highest point.
E)  The horizontal acceleration is always zero and the vertical acceleration is always a non-zero constant downward.F) B) and C)
G) All of the above

Question 20

A football kicker is attempting a field goal from 
Out.The ball is kicked and just clears the lower bar with a time of flight of 
If the angle of the kick was 45°,what was the initial speed of the ball,assuming no air resistance?

Accepted Answer

A)  21.5 m/s
B)  19.7 m/s
C)  2.2 m/s
D)  39 m/sE) A) and B)
F) A) and C)

Exam 4: Two-Dimensional Kinematics

The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively.If there is no air resistance,how long does it take the football to reach the top of its trajectory?

Correct Answer
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Correct Answer
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A hobbyist launches a projectile from ground level on a horizontal plain.It reaches a maximum height of 72.3 m and lands 111 m from the launch point,with no appreciable air resistance.What was the angle of launch if g = 9.80 m/s²?

Correct Answer
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A projectile is fired at an angle above the horizontal at a location where g = 9.8 m/s².The initial x and y components of its velocity are 86.6 m/s and 50 m/s respectively.At what angle was the projectile fired above the horizontal?

Correct Answer
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A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically.Which object is traveling faster when it hits the level ground below if neither of them experiences any air resistance?

Correct Answer
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Correct Answer
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A football kicker is attempting a field goal from Out.The ball is kicked and just clears the lower bar with a time of flight of If the angle of the kick was 45°,what was the initial speed of the ball,assuming no air resistance?

Correct Answer
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A player kicks a soccer ball in a high arc toward the opponent's goal.At the highest point in its trajectory

Correct Answer
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A boy kicks a football from ground level with an initial velocity of 20 m/s at an angle of 30° above the horizontal.What is the horizontal distance to the point where the football hits the ground if we neglect air resistance?

Correct Answer
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An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 35° above the horizontal.How long does the athlete stay in the air,assuming no significant air resistance?

Correct Answer
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A projectile is fired from ground level with a speed of 150 m/s at an angle 30° above the horizontal on an airless planet where g = 10.0 m/s².What is the horizontal component of its velocity after 4.0 s?

Correct Answer
verified

A pilot drops a package from a plane flying horizontally at a constant speed.Neglecting air resistance,when the package hits the ground the horizontal location of the plane will

Correct Answer
verified

Correct Answer
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A boulder rolls off of a very high cliff and experiences no significant air resistance.While it is falling,its trajectory is never truly vertical.

Correct Answer
verified

In an air-free chamber,a pebble is thrown horizontally,and at the same instant a second pebble is dropped from the same height.Compare the times of fall of the two pebbles.

Correct Answer
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A ball is thrown at an original speed of 8.0 m/s at an angle of 35° above the horizontal.If there is no air resistance,what is the speed of the ball when it returns to the same horizontal level?

Correct Answer
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An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 55° with the vertical.What is the length of the athlete's jump if air resistance is of no significance?

Correct Answer
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A hockey puck slides off the edge of a platform with an initial velocity of 20 m/s horizontally.The height of the platform above the ground is 2.0 m.What is the magnitude of the velocity of the puck just before it touches the ground? You can neglect air resistance.

Correct Answer
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Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice. )

Correct Answer
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Correct Answer
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Exam 4: Two-Dimensional Kinematics

The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s respectively.If there is no air resistance,how long does it take the football to reach the top of its trajectory?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A hobbyist launches a projectile from ground level on a horizontal plain.It reaches a maximum height of 72.3 m and lands 111 m from the launch point,with no appreciable air resistance.What was the angle of launch if g = 9.80 m/s2?

Correct AnswerverifiedShow Answer

A projectile is fired at an angle above the horizontal at a location where g = 9.8 m/s2.The initial x and y components of its velocity are 86.6 m/s and 50 m/s respectively.At what angle was the projectile fired above the horizontal?

Correct AnswerverifiedShow Answer

A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically.Which object is traveling faster when it hits the level ground below if neither of them experiences any air resistance?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A football kicker is attempting a field goal from Out.The ball is kicked and just clears the lower bar with a time of flight of If the angle of the kick was 45°,what was the initial speed of the ball,assuming no air resistance?

Correct AnswerverifiedShow Answer

A player kicks a soccer ball in a high arc toward the opponent's goal.At the highest point in its trajectory

Correct AnswerverifiedShow Answer

A boy kicks a football from ground level with an initial velocity of 20 m/s at an angle of 30° above the horizontal.What is the horizontal distance to the point where the football hits the ground if we neglect air resistance?

Correct AnswerverifiedShow Answer

An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 35° above the horizontal.How long does the athlete stay in the air,assuming no significant air resistance?

Correct AnswerverifiedShow Answer

A projectile is fired from ground level with a speed of 150 m/s at an angle 30° above the horizontal on an airless planet where g = 10.0 m/s2.What is the horizontal component of its velocity after 4.0 s?

Correct AnswerverifiedShow Answer

A pilot drops a package from a plane flying horizontally at a constant speed.Neglecting air resistance,when the package hits the ground the horizontal location of the plane will

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A boulder rolls off of a very high cliff and experiences no significant air resistance.While it is falling,its trajectory is never truly vertical.

Correct AnswerverifiedShow Answer

In an air-free chamber,a pebble is thrown horizontally,and at the same instant a second pebble is dropped from the same height.Compare the times of fall of the two pebbles.

Correct AnswerverifiedShow Answer

A ball is thrown at an original speed of 8.0 m/s at an angle of 35° above the horizontal.If there is no air resistance,what is the speed of the ball when it returns to the same horizontal level?

Correct AnswerverifiedShow Answer

An athlete competing in the long jump leaves the ground with a speed of 9.14 m/s at an angle of 55° with the vertical.What is the length of the athlete's jump if air resistance is of no significance?

Correct AnswerverifiedShow Answer

A hockey puck slides off the edge of a platform with an initial velocity of 20 m/s horizontally.The height of the platform above the ground is 2.0 m.What is the magnitude of the velocity of the puck just before it touches the ground? You can neglect air resistance.

Correct AnswerverifiedShow Answer

Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice. )

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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A hobbyist launches a projectile from ground level on a horizontal plain.It reaches a maximum height of 72.3 m and lands 111 m from the launch point,with no appreciable air resistance.What was the angle of launch if g = 9.80 m/s²?

Correct Answer
verified

A projectile is fired at an angle above the horizontal at a location where g = 9.8 m/s².The initial x and y components of its velocity are 86.6 m/s and 50 m/s respectively.At what angle was the projectile fired above the horizontal?

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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A projectile is fired from ground level with a speed of 150 m/s at an angle 30° above the horizontal on an airless planet where g = 10.0 m/s².What is the horizontal component of its velocity after 4.0 s?

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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