In introductory mechanics, what does acceleration measure?

• A. The total distance traveled divided by time
• B. The rate of change of position with respect to time
• C. The net force divided by time
• D. The rate of change of velocity with respect to time

Answer: (D)

Verified step by step guidance

1. Understand that acceleration is a vector quantity that describes how an object's velocity changes over time.
2. Recall that velocity itself is the rate of change of position with respect to time, so acceleration measures how this velocity changes.
3. Express acceleration mathematically as the derivative of velocity with respect to time: \( a = \frac{d v}{d t} \).
4. Recognize that acceleration is not simply distance divided by time (which relates to average speed) nor net force divided by time (which relates to force and momentum concepts).
5. Conclude that acceleration measures the rate of change of velocity with respect to time, indicating how quickly an object speeds up, slows down, or changes direction.