Chapter 2 Physics                                                         Name:

1D-Vertical Motion (affected by gravity-use 9.8 m/s2)

 

Use all the steps of problem solving and show work to find the answers for the following

just like you would if it were not multiple choice.

 

 1. A rock is thrown straight down with an initial velocity of 14.5 m/s from a cliff.  What is the rock’s displacement after 2.0 s? (Acceleration due to gravity is 9.80 m/s2.)

 

a. 28 m

b. 49 m

c. 55 m

            d. 64 m                                                                                                       b

 

2.  A rock is thrown straight up with an initial velocity of 24.5 m/s.What maximum height will the rock reach before starting to fall downward? (Take acceleration due to gravity as 9.80 m/s2.)

 

a. 9.80 m

b. 19.6 m

c. 24.5 m

            d. 30.6 m                                                                                                      d

 

3.  A rock is thrown straight up with an initial velocity of 19.6 m/s. What time interval elapses between the rock’s being thrown and its return to the original launch point? (Acceleration due to gravity is 9.80 m/s2.)

 

a. 4.00 s

            b. 5.00 s

            c. 8.00 s

         d. 10.0 s                                                                                                  a

4.  Two objects of different mass are released simultaneously from the top of a 20-m tower and fall to the ground. If air resistance is negligible, which statement best applies?  Use book.

 

a. The greater mass hits the ground first.

b. Both objects hit the ground together.

c. The smaller mass hits the ground first.

               d. No conclusion can be made with the information given.

 

5.   A baseball catcher throws a ball vertically upward and catches it in the same spot when it returns to his mitt. At what point in the ball’s path does it experience zero velocity and non‑zero acceleration at the same time?  Use book.

 

a. midway on the way up

b. at the top of its trajectory

c. the instant it leaves the catcher’s hand

d. the instant before it arrives in the catcher’s mitt

 

 

6. A baseball is released at rest from the top of the Washington Monument. It hits the ground after falling for 6.0 s. What was the height from which the ball was dropped? (g = 9.8 m/s2 and assume air resistance is negligible)

 

a. 1.5 x 102 m

b. 1.8 x 102 m

c. 1.1 x 102 m

d. 2.1 x 102 m                                                                                             b

 

7.   A rock, released at rest from the top of a tower, hits the ground after 1.5 s. What is the speed of the rock as it hits the ground? (g = 9.8 m/s2 and air resistance is negligible)

 

a. 15 m/s

b. 20 m/s

c. 31 m/s

                  d. 39 m/s                                                                                                  a

 

8.   Omar throws a rock down with speed 12 m/s from the top of a tower. The rock hits the ground after 2.0 s. What is the height of the tower? (air resistance is negligible)

 

a. 20 m

b. 24 m

c. 44 m

d. 63 m                                                                                                             c

 

9.   Gwen releases a rock at rest from the top of a 40-m tower. If g = 9.8 m/s2 and air resistance is negligible, what is the speed of the rock as it hits the ground?

 

a. 28 m/s

b. 30 m/s

c. 56 m/s

d. 784 m/s                                                                                                        a

 

10.        John throws a rock down with speed 14 m/s from the top of a 30-m tower. If g = 9.8 m/s2 and air resistance is negligible, what is the rock’s speed just as it hits the ground?

 

a. 12 m/s

b. 28 m/s

c. 350 m/s

d. 784 m/s                                                                                                        b

 

11. The value of an object’s acceleration may be characterized in equivalent words by which of the following?  Use book.

 

a. displacement

b. rate of change of displacement

c. velocity

d. rate of change of velocity