Aracing car whose mass is 1.2 x 10^3 kg is travelling at 8.9 m/s. it stops with a constant deceleration in a distance of 1.8x10^1 m. what force must the brakes apply to the car if the friction in the car’s engine is 1.8 x 10^3 n.

given that initial speed of the car is

now after travelling the distance d = 1.8 * 10^1 m the car will stop

so here we can use kinematics to find the acceleration of car

here we have

net force applied due to brakes of car is given by Newton's II law

here we have

mass = 1.2 * 10^3 kg

now we can say

So the force applied due to brakes is given as above