A stone is thrown downward from a cliff.Take "up" to be the positive direction.Which of the following statements is true about the stone?
A) The velocity is negative,the acceleration is negative,and the speed is negative.
B) The velocity is positive,the acceleration is negative,and the speed is positive.
C) The velocity is negative,the acceleration is negative,and the speed is positive.
D) The velocity is positive,the acceleration is positive,and the speed is positive.

Question

Quizplus · Accepted Answer

Since the stone is thrown downward, its velocity is negative (in the opposite direction of "up"). Also, since the stone is accelerating due to the force of gravity, its acceleration is also negative (pointing downwards). However, the speed of the stone is positive, as it is moving downwards with a nonzero velocity.

A Stone Is Thrown Downward from a Cliff