Question

A child sleds down a hill with an acceleration of 2.94 m/s2. If her initial speed is 0.0 m/s and her final speed is 17.5 m/s, how long does it take her to travel from the top of the hill to the bottom?

Answer 1

Answer:

The child will take 5.952 seconds to travel from the top of the hill to the bottom.

Explanation:

Given that the child accelerates uniformly and that both initial ($v_{o}$) and final speeds ($v_{f}$), measured in meters per second, and acceleration ($a$), measured in meters per square second, are known, we proceed to use the following kinematic equation to determine the time taken to travel from the top of the hill to the bottom ($t$), measured in seconds, is:

$t = \frac{v_{f}-v_{o}}{a}$ (1)

If we know that $v_{o} = 0\,\frac{m}{s}$, $v_{f} = 17.5\,\frac{m}{s}$ and $a = 2.94\,\frac{m}{s^{2}}$, then the time taken is:

$t = \frac{17.5\,\frac{m}{s}-0\,\frac{m}{s} }{2.94\,\frac{m}{s^{2}} }$

$t = 5.952\,s$

The child will take 5.952 seconds to travel from the top of the hill to the bottom.