Question

a car of mass 1200 kg is bought to rest from a speed of 60ms^1by a constant breaking force of 6000 N calculate the retardation and the time in which the car comes to rest

ans in detail

final ans is 5ms^2,12s

Answer 1

f=m (v-u)/t -6000=1200 (0-60)/t -6000=-72000/t t=-72000/-6000  =12s  a=v-u/t  =0-60/12  =-60/12  =-5m/s^2  

Answer 2

Answer:

v=u+at

0=60+a12

0-60=12a

a=-5m/s^2