A tennis racket hits a tennis ball. The racket has a mass that is four times greater than the tennis ball. Compared to the force exerted on the ball by the racket, the force exerted on the racket by the ball is A.) four times smaller
B.) the same
C.) 16 times smaller
D.) four times greater

Aknife blade is a(n) a. lever b. screw c. wedge d. inclined plane

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.