Name: __________________________ Date: _____________
1. 
A football is kicked at an angle ? with respect to the horizontal. Which one of the following statements best describes the acceleration of the football during this event if air resistance is neglected?
A. 
The acceleration is zero m/s^{2} at all times. 
B. 
The acceleration is 9.8 m/s^{2} at all times. 
C. 
The acceleration is zero m/s^{2} when the football has reached the highest point in its trajectory. 
D. 
The acceleration is positive as the football rises, and it is negative as the football falls. 
E. 
The acceleration starts at 9.8 m/s^{2} and drops to some constant lower value as the ball approaches the ground. 

2. 
A baseball is hit upward and travels along a parabolic arc before it strikes the ground. Which one of the following statements is necessarily true?
A. 
The acceleration of the ball decreases as the ball moves upward. 
B. 
The velocity of the ball is zero m/s when the ball is at the highest point in the arc. 
C. 
The acceleration of the ball is zero m/s^{2} when the ball is at the highest point in the arc. 
D. 
The xcomponent of the velocity of the ball is the same throughout the ball's flight. 
E. 
The velocity of the ball is a maximum when the ball is at the highest point in the arc. 

3. 
A physics student standing on the edge of a cliff throws a stone vertically downward with an initial speed of 10.0 m/s. The instant before the stone hits the ground below, it is traveling at a speed of 30.0 m/s. If the physics student were to throw the rock horizontally outward from the cliff instead, with the same initial speed of 10.0 m/s, what is the magnitude of the velocity of the stone just before it hits the ground?
E. 
The height of the cliff must be specified to answer this question. 

4. 
A tennis ball is thrown from ground level with velocity v_{o} directed 30° above the horizontal. If it takes the ball 1.0 s to reach the top of its trajectory, what is the magnitude of the initial velocity?

A projectile is fired at an angle of 60.0° above the horizontal with an initial speed of 30.0 m/s.
Reference: Ref 33
5. 
What is the magnitude of the horizontal component of the projectile's displacement at the end of 2 s?

A projectile is fired at an angle of 60.0° above the horizontal with an initial speed of 30.0 m/s.
Reference: Ref 33
6. 
How long does it take the projectile to reach the highest point in its trajectory?

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
7. 
Determine the initial speed of the projectile.

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
8. 
At what angle is the projectile fired (measured with respect to the horizontal)?

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
9. 
Approximately how long does it take the projectile to reach the highest point in its trajectory?

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
10. 
What is the speed of the projectile when it is at the highest point in its trajectory?

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
11. 
What is the acceleration of the projectile when it reaches its maximum height?
D. 
less than 9.8 m/s^{2 }and nonzero. 
E. 
Its magnitude is 9.8 m/s^{2}; and its direction is changing. 

A projectile is fired from a gun and has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
Reference: Ref 34
12. 
What is the magnitude of the projectile's velocity just before it strikes the ground?

13. 
A springloaded gun is aimed horizontally and is used to launch identical balls with different initial speeds. The gun is at a fixed position above the floor. The balls are fired one at a time. If the speed of the second projectile fired is twice the speed of the first projectile fired, how is the horizontal range (denoted R in the figure) affected?
A. 
The range for both projectiles will be the same. 
B. 
The range of the second projectile will be half as much as that of the first projectile. 
C. 
The range of the second projectile will be twice as large as that of the first projectile. 
D. 
The range of the second projectile is about 1.4 times larger than that of the first projectile. 
E. 
The range of the second projectile will be smaller than that of the first projectile by a factor of 1.4. 

14. 
A projectile is fired horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its displacement 3.0 s after it is fired?

A shell is fired with a horizontal velocity in the positive
x direction from the top of an 80m high cliff. The shell strikes the ground 1330 m from the base of the cliff.
Reference: Ref 35
15. 
Determine the initial speed of the shell.

A shell is fired with a horizontal velocity in the positive
x direction from the top of an 80m high cliff. The shell strikes the ground 1330 m from the base of the cliff.
Reference: Ref 35
16. 
What is the speed of the shell as it hits the ground?

17. 
A cannonball is aimed 30.0° above the horizontal and is fired with an initial speed of 125 m/s at ground level. How far away from the cannon will the cannonball hit the ground?

18. 
A basketball is launched with an initial speed of 8.0 m/s and follows the trajectory shown. The ball enters the basket 0.96 s after it is launched. What are the distances x and y? Note: The drawing is not to scale.

19. 
A bullet is aimed at a target on the wall a distance L away from the firing position. Because of gravity, the bullet strikes the wall a distance ? y below the mark as suggested in the figure. Note: The drawing is not to scale.If the distance L were half as large, and the bullet had the same initial velocity, how would ? y be affected?
B. 
It will be half as large. 
C. 
It will be four times larger. 
D. 
It will be one fourth as large. 
E. 
It is not possible to determine unless numerical values are given for the distances. 

A projectile is fired horizontally with an initial speed of 50.0 m/s. Neglect air resistance.
Reference: Ref 39
20. 
What is the magnitude of the displacement of the projectile 3.00 s after it is fired?

A projectile is fired horizontally with an initial speed of 50.0 m/s. Neglect air resistance.
Reference: Ref 39
21. 
What is the speed of the projectile 3.00 s after it is fired?

22. 
A basketball player is running at a constant speed of 2.5 m/s when he tosses a basketball upward with a speed of 6.0 m/s. How far does the player run before he catches the ball? Ignore air resistance.
C. 
The ball cannot be caught because it will fall behind the player. 

23. 
A puck slides across a smooth, level tabletop at height H at a constant speed v_{o}. It slides off the edge of the table and hits the floor a distance x away as shown in the figure. What is the relationship between the distances x and H?

24. 
An arrow is shot horizontally from a height of 4.9 m above the ground. The initial speed of the arrow is 45 m/s. Neglecting friction, how long will it take the arrow to hit the ground?
