Question

1. a jogger accelerates at a constant rate as she travels 5.0 meters along a straight track from point a to point b, as shown in the diagram below. if her speed was 2.0 meters per second at point a and will be 3.0 meters per second at point b, how long will it take her to go from a to b? a) 1.0 s b) 2.0 s c) 3.3 s d) 4.2 s

Explanation:

Step1: Find the average speed

The formula for average speed \(v_{avg}=\frac{v_{i} + v_{f}}{2}\), where \(v_{i}\) is the initial speed and \(v_{f}\) is the final speed.
Given \(v_{i} = 2.0\space m/s\) and \(v_{f}=3.0\space m/s\), then \(v_{avg}=\frac{2.0 + 3.0}{2}=\frac{5.0}{2}=2.5\space m/s\)

Step2: Calculate the time

The formula for time \(t=\frac{d}{v_{avg}}\), where \(d\) is the distance.
Given \(d = 5.0\space m\) and \(v_{avg}=2.5\space m/s\), then \(t=\frac{5.0}{2.5}=2.0\space s\)

Answer:

B. \(2.0\space s\)