A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance?
A) 6.67 s
B) 15.0 s
C) 9.80 s
D) 10.2 s
E) 13.3 s

Question

Quizplus · Accepted Answer

Using the equation $ v = u + at $ and $ s = ut + \frac{1}{2}at^2 $, where $ u = 0 $, $ v = 9.00 \, \text{m/s} $, and $ s = 60.0 \, \text{m} $, we find $ a = \frac{v^2}{2s} = \frac{(9.00)^2}{2 \times 60.0} = 0.675 \, \text{m/s}^2 $. Then, using $ v = at $, $ t = \frac{v}{a} = \frac{9.00}{0.675} = 13.33 \, \text{s} $.

A Runner Maintains Constant Acceleration After Starting from Rest as She