Identify whether the following statements describe a change in acceleration. explain your response.

a. A car stopped at a stop sign.  

d. A person running at 5 meters/second along a curving path

Explanation:

There is acceleration in all cases velocity changes. In options b and c the speed is constant, then there is no acceleration. In option a, the car was moving and then stop, therefore, its speed decrease to zero, and that represent an acceleration. In option d, the magnitude of the velocity doesn't change, nevertheless its direction changes along the curving path (remember that velocity is a vector quantity), therefore, the person receive centripetal acceleration .

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.

b would be the answer