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

Explanation

We are given: `m = 20 kg implies F= -50 N implies u= 15ms^(-1) implies v=0`
We are to calculate: Stopping time, t
We know that, `F= ma implies a= (F)/(m)= (-50)/(20)= -2.5 ms^(-2)`
Also, `v= u+at implies 0+ 15+ (-2.5)t implies t= 6s`