Question

A glider of mass 5.0 kg hits the end of a horizontal rail and bounces off with the same speed, in the opposite direction. The collision is elastic and takes place in a time interval of 0.2s, with an average force of 100N. What was the speed, in m/s, of the glider

Answer 1

To solve the exercise it is necessary to apply the concepts given in Newton's second law and the equations of motion description.

Let's start by defining acceleration based on speed and time, that is

$a = \frac{v}{t}$

On the other hand according to Newton's second law we have to

F=ma

where

m= Mass

a = Acceleration

Replacing the value of acceleration in this equation we have

$F=m(\frac{v}{t})$

Substituting with our values we have

$100N=(5Kg)\frac{v}{0.2}$

Re-arrange to find v

$v=\frac{100*0.2}{5}$

$v = 2m/s$

Therefore the speed of the glider is 2m/s