Question

A car is moving at a velocity of 72 Km/h. Suddenly brakes are applied so as to stop the car after 10 m. Find the force exerted by the brakes on the car. (If the total mass of car and passengers is equal to 800 Kg).

Answer 1

Velocity of the car = 72 km/h

Now, convert it into m/s

(72 x 5/18) m/s = 20 m/s

time = 10 minutes = (10 x 60) s = 600 s

Mass of the car along with passenger = 800 kg

F=ma

Force = mass x acceleration

Mass = 800 kg

acceleration, a = v-u/t

a = 0-20/600 m/s²

a = -20/600 m/s²

a = -1/30 m/s²

Now, put this on F= ma

F = 800 x -1/30

F = 26.6 N

BE BRAINLY