Question 1

A rocket takes off vertically from the launchpad with no initial velocity but a constant upward acceleration of 2.25 m/s². At 15.4 s after blastoff, the engines fail completely so the only force on the rocket from then on is the pull of gravity. (a) What is the maximum height the rocket will reach above the launchpad? (b) How fast is the rocket moving at the instant before it crashes onto the launchpad? (c) How long after engine failure does it take for the rocket to crash onto the launchpad?

Accepted Answer

The answer of A rocket takes off vertically from the...

Question 2

A ball rolls across a floor with an acceleration of 0.100 m/s2 in a direction opposite to its velocity. The ball has a velocity of 4.00 m/s after rolling a distance 6.00 m across the floor. What was the initial speed of the ball?

Accepted Answer

A)  4.15 m/s 
B)  5.85 m/s 
C)  4.60 m/s 
D)  5.21 m/s 
E)  3.85 m/s

Question 3

The position of an object as a function of time is given by x =bt2 - ct, where b = 2.0 m/s2 and
C = 6.7 m/s, and x and t are in SI units. What is the instantaneous velocity of the object when t = 2.2?

Accepted Answer

A)  1.7 m/s 
B)  2.1 m/s 
C)  2.3 m/s 
D)  2.7 m/s

Question 4

A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance?

Accepted Answer

A)  6.67 s 
B)  15.0 s 
C)  9.80 s 
D)  10.2 s 
E)  13.3 s

Question 5

The velocity of an object as a function of time is given by v(t) = 2.00 m/s + (3.00 m/s) t - (1.0 m/s2) t2. Determine the instantaneous acceleration of the object at time t = 5.00 s.

Accepted Answer

A)  -8.00 m/s2 
B)  -7.00 m/s2 
C)  2.00 m/s2 
D)  0.00 m/s2 
E)  -2.00 m/s2

Question 6

The figure shows a graph of the velocity as a function of time for a basketball player traveling up and down the court in a straight-line path. for the 10 s shown on the graph, find
(a) the net displacement of the player.
(b) the total distance run by the player.

Accepted Answer

The answer of The figure shows a graph of the...

Question 7

Which one of the following graphs could possibly represent the vertical position as a function of time for an object in free fall?

Accepted Answer

A)   
B)   
C)   
D)   
E)

Question 8

When can we be certain that the average velocity of an object is always equal to its instantaneous velocity?

Accepted Answer

A)  always 
B)  never 
C)  only when the velocity is constant 
D)  only when the acceleration is constant 
E)  only when the acceleration is changing at a constant rate

Question 9

A rock is dropped from the top of a vertical cliff and takes 3.00 s to reach the ground below the cliff. A second rock is thrown vertically from the cliff, and it takes this rock 2.00 s to reach the ground below the cliff from the time it is released. With what velocity was the second rock thrown, assuming no air resistance?

Accepted Answer

A)  4.76 m/s upward 
B)  5.51 m/s downward 
C)  12.3 m/s upward 
D)  4.76 m/s downward 
E)  12.3 m/s downward

Question 10

Arthur and Betty start walking toward each other when they are 100 m apart. Arthur has a speed of 3.0 m/s and Betty has a speed of 2.0 m/s. Their dog, Spot, starts by Arthur's side at the same time and runs back and forth between them at 5.0 m/s. By the time Arthur and Betty meet, what distance has Spot run?

Accepted Answer

The answer of Arthur and Betty start walking toward each...

Question 11

Two identical stones are dropped from rest and feel no air resistance as they fall. Stone A is dropped from height h, and stone B is dropped from height 2h. If stone A takes time t to reach the ground, stone B will take time

Accepted Answer

A)  4t. 
B)  2t. 
C)  t  . 
D)  t/  . 
E)  t/2.

Question 12

A foul ball is hit straight up into the air with a speed of 30.0 m/s.
(a) Calculate the time required for the ball to rise to its maximum height.
(b) Calculate the maximum height reached by the ball.
(c) Determine the time at which the ball pass a point 25.0 m above the point of contact between the bat and ball.
(d) Explain why there are two answers to part (c).

Accepted Answer

The answer of A foul ball is hit straight up...

Question 13

If the fastest you can safely drive is 65 mi/h what is the longest time you can stop for dinner if you must travel 541 m in 9,6 h total?

Accepted Answer

A)  1.0 h 
B)  1.3 h 
C)  1.4 h 
D)  You can't stop at all.

Question 14

The position of an object as a function of time is given by  
where  
  
c = 60 m/s and d = 7.0 m.
(a) Find the instantaneous acceleration at t =2.4 s.
(b) Find the average acceleration over the first 2.4 seconds.

Accepted Answer

The answer of The position of an object as a...

Question 15

An object starts from rest at time t = 0.00 s and moves in the +x direction with constant acceleration. The object travels 12.0 m from time t = 1.00 s to time t = 2.00 s. What is the acceleration of the object?

Accepted Answer

A)  -12.0 m/s2 
B)  24.0 m/s2 
C)  -4.00 m/s2 
D)  4.00 m/s2 
E)  8.00 m/s2

Question 16

The figure shows the position of an object as a function of time. During the time interval from time
t = 0.0 s and time t = 9.0 s,
(a) what is the length of the path the object followed?
(b) what is the displacement of the object?

Accepted Answer

The answer of The figure shows the position of an...

Question 17

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

Accepted Answer

A)  The acceleration of the ball is upward while it is traveling up and downward while it is traveling down. 
B)  The acceleration of the ball is downward while it is traveling up and upward while it is traveling down. 
C)  The acceleration is downward during the entire time the ball is in the air. 
D)  The acceleration of the ball is downward while it is traveling up and downward while it is traveling down but is zero at the highest point when the ball stops.

Question 18

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2. After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?

Accepted Answer

A)  487 m 
B)  327 m 
C)  320 m 
D)  408 m 
E)  160 m

Question 19

A rock is thrown directly upward from the edge of the roof of a building that is 66.2 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Neglect any effects of air resistance. With what speed was the rock thrown?

Accepted Answer

The answer of A rock is thrown directly upward from...

Exam 2: Kinematics in One Dimension

A ball rolls across a floor with an acceleration of 0.100 m/s² in a direction opposite to its velocity. The ball has a velocity of 4.00 m/s after rolling a distance 6.00 m across the floor. What was the initial speed of the ball?

The position of an object as a function of time is given by x =bt² - ct, where b = 2.0 m/s² and C = 6.7 m/s, and x and t are in SI units. What is the instantaneous velocity of the object when t = 2.2?

A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance?

The velocity of an object as a function of time is given by v(t) = 2.00 m/s + (3.00 m/s) t - (1.0 m/s²) t². Determine the instantaneous acceleration of the object at time t = 5.00 s.

The figure shows a graph of the velocity as a function of time for a basketball player traveling up and down the court in a straight-line path. for the 10 s shown on the graph, find (a) the net displacement of the player. (b) the total distance run by the player.

Which one of the following graphs could possibly represent the vertical position as a function of time for an object in free fall?

When can we be certain that the average velocity of an object is always equal to its instantaneous velocity?

Two identical stones are dropped from rest and feel no air resistance as they fall. Stone A is dropped from height h, and stone B is dropped from height 2h. If stone A takes time t to reach the ground, stone B will take time

If the fastest you can safely drive is 65 mi/h what is the longest time you can stop for dinner if you must travel 541 m in 9,6 h total?

The position of an object as a function of time is given by where c = 60 m/s and d = 7.0 m. (a) Find the instantaneous acceleration at t =2.4 s. (b) Find the average acceleration over the first 2.4 seconds.

An object starts from rest at time t = 0.00 s and moves in the +x direction with constant acceleration. The object travels 12.0 m from time t = 1.00 s to time t = 2.00 s. What is the acceleration of the object?

The figure shows the position of an object as a function of time. During the time interval from time t = 0.0 s and time t = 9.0 s, (a) what is the length of the path the object followed? (b) what is the displacement of the object?

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s². After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?

A rock is thrown directly upward from the edge of the roof of a building that is 66.2 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Neglect any effects of air resistance. With what speed was the rock thrown?

Exam 2: Kinematics in One Dimension

A ball rolls across a floor with an acceleration of 0.100 m/s2 in a direction opposite to its velocity. The ball has a velocity of 4.00 m/s after rolling a distance 6.00 m across the floor. What was the initial speed of the ball?

The position of an object as a function of time is given by x =bt2 - ct, where b = 2.0 m/s2 and C = 6.7 m/s, and x and t are in SI units. What is the instantaneous velocity of the object when t = 2.2?

A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance?

The velocity of an object as a function of time is given by v(t) = 2.00 m/s + (3.00 m/s) t - (1.0 m/s2) t2. Determine the instantaneous acceleration of the object at time t = 5.00 s.

The figure shows a graph of the velocity as a function of time for a basketball player traveling up and down the court in a straight-line path. for the 10 s shown on the graph, find (a) the net displacement of the player. (b) the total distance run by the player.

Which one of the following graphs could possibly represent the vertical position as a function of time for an object in free fall?

When can we be certain that the average velocity of an object is always equal to its instantaneous velocity?

Two identical stones are dropped from rest and feel no air resistance as they fall. Stone A is dropped from height h, and stone B is dropped from height 2h. If stone A takes time t to reach the ground, stone B will take time

If the fastest you can safely drive is 65 mi/h what is the longest time you can stop for dinner if you must travel 541 m in 9,6 h total?

The position of an object as a function of time is given by where c = 60 m/s and d = 7.0 m. (a) Find the instantaneous acceleration at t =2.4 s. (b) Find the average acceleration over the first 2.4 seconds.

An object starts from rest at time t = 0.00 s and moves in the +x direction with constant acceleration. The object travels 12.0 m from time t = 1.00 s to time t = 2.00 s. What is the acceleration of the object?

The figure shows the position of an object as a function of time. During the time interval from time t = 0.0 s and time t = 9.0 s, (a) what is the length of the path the object followed? (b) what is the displacement of the object?

A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct?

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2. After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?

A rock is thrown directly upward from the edge of the roof of a building that is 66.2 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Neglect any effects of air resistance. With what speed was the rock thrown?

A ball rolls across a floor with an acceleration of 0.100 m/s² in a direction opposite to its velocity. The ball has a velocity of 4.00 m/s after rolling a distance 6.00 m across the floor. What was the initial speed of the ball?

The position of an object as a function of time is given by x =bt² - ct, where b = 2.0 m/s² and C = 6.7 m/s, and x and t are in SI units. What is the instantaneous velocity of the object when t = 2.2?

The velocity of an object as a function of time is given by v(t) = 2.00 m/s + (3.00 m/s) t - (1.0 m/s²) t². Determine the instantaneous acceleration of the object at time t = 5.00 s.

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s². After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach?