A constant retarding force of 50 N is applied to a body of mass 20 kg moving initially with a speed of `15 ms^(-1)` .How long does the body take to stop ?

Explanation

Here , F = - 50 N , m = 20 kg
` mu = 15 m//s , v = 0 , t = ?`
From F = ma
` a = F/m = (-50)/20 = - 2.5 m//s^(2)`
From `v = u + "at"`
` 0 - 15 - 2.5 t`
` t = 15/(2.5) = 6s`