How much force is needed to slow down a 15 kg car traveling at 60 m/s to 15 m/s in 10 seconds?

The force needed to slow down the car is, F = 67.5 N

Explanation:

Given data,

The mass of the car, m = 15 kg

The initial velocity of the car, V = 60 m/s

The final velocity of the car, v = 15 m/s

The time period of deceleration, t = 10 s

The difference in the momentum of the car is,

                                     mV - mv = 15(60 - 15)

                                                    = 675 kg m/s

The rate of change in momentum of the car gives the force acting on it.

                                    F = (mV - mu) / t

Substituting the values,

                                   F = 675 / 10

                                      = 67.5 N

Hence, the force needed to slow down the car is, F = 67.5 N

increases it

it is a negative acceleration