Question

A car of mass 2400 kg moving with a velocity of 20 m s^-1 is stopped in 10 seconds on applying brakes. Calculate the retardation and the retarding force.

Answer 1

Let us first calculate the retardation = `((v-u))/t`
= `((0-20))/10`
= `(-20)/10`
= `(-20)/10`
= `-2  "m/s"^2`
Now, we are going to find retarding force = mass × acceleration
                 = 2400 kg × −2
                  = −4800 N
The negative sign implies that the force on the car is acting opposite to the motion of the car.