VIII. You are throwing a ball straight up in the air. At the highest point, the ball's

A. velocity and acceleration are zero.

B. velocity is nonzero but its acceleration is zero.

C. acceleration is nonzero, but its velocity is zero.

D. velocity and acceleration are both nonzero.

E. None of above.                              Ans. C

IX. A railroad car traveling at a speed of v strikes and couples with a caboose of the same mass at rest. What is the speed of the final combination?

A. 

B. 2v

C. 

D. 

E. 0                                         Ans. A

 

X. Two blocks on a frictionless horizontal surface are in contact with each other, as shown in the figure. A force of 30N is applied to block A, what is the interacting force exerted by block B on block A?

A. 10N

B. 0N

C. 30N

D. 20N

E. None of above                            Ans. D