Question

which sections of the graph show that there is an acceleration that is changing?
o a q and r only
o b. q, r and s only
o c. r and s only
o d. p, q, r and s

Explanation:

Step1: Recall the relationship between speed - time graph and acceleration

Acceleration \(a=\frac{\Delta v}{\Delta t}\), which is the slope of the speed - time graph. If the slope is changing, then the acceleration is changing.

Step2: Analyze each section

• Section P: The speed is \(0\) (constant), so the slope \(a = 0\) (constant).
• Section Q: The slope of the speed - time graph is increasing. Since \(a=\frac{\Delta v}{\Delta t}\) (slope), the acceleration is changing.
• Section R: The slope of the speed - time graph is decreasing. Since \(a=\frac{\Delta v}{\Delta t}\) (slope), the acceleration is changing.
• Section S: The slope of the speed - time graph (acceleration) is negative and the magnitude of the slope is constant.

Answer:

A. Q and R only