Question

which of the following objects is accelerating? a a car driving southwest at a constant speed of 35 mph. b a car driving in a northwest at a constant speed of 35 mph. c a car driving in a circle at a constant speed of 35 mph. d a car driving south at a constant speed of 45 mph.

Explanation:

Step1: Recall acceleration definition

Acceleration is a change in velocity. Velocity is a vector with speed and direction.

Step2: Analyze option a

Constant speed and constant direction, no acceleration.

Step3: Analyze option b

Constant speed and constant direction, no acceleration.

Step4: Analyze option c

Constant speed but changing direction (moving in a circle), so there is acceleration.

Step5: Analyze option d

Constant speed and constant direction, no acceleration.

Answer:

c. A car driving in a circle at a constant speed of 35 mph.