Question

A child goes down a slide, starting from rest. If the length of the slide is 2 m and it takes the child 3 seconds to go down the slide, what is the child’s acceleration?

Answer 1

We can find the child's acceleration from the kinematic equation:

$$d = v_0t+ \dfrac{1}{2}at^2,$$

here, $d = 2 \ m$ is the distance traveled by the child, $v_0 = 0 \ ms^{-1}$ is the initial velocity of the child, $a$ is the child's acceleration and $t = 3 \ s$ is the time during which the child reaches down the slide.

Then, from this equation we can calculate the child's acceleration:

$$a = \dfrac{2d}{t^2} = \dfrac{2 \cdot 2 \ m}{(3 \ s)^2} = 0.44 \ ms^{-2}.$$

Answer:

$a = 0.44 \ ms^{-2}.$