Question

A scooter is moving with an initial velocity of 90km per hour and it takes 10s to stop it,better the brakes are applied. Calculate the force exerted by the brakes on the scooter, if it's mass along with the rider is 200kg. What would be the force if the mass is halved?

Answer 1

U = 90 m/s = 25 m/s
v = 0
t = 10 sec
as, v = u +at
⇒0 = 25 + 10a
⇒10a = -25
⇒a = -2.5 m/s²
Force = mass×acceleration
=200×(-2.5)
= - 500 N
negative shows the direction of force is opp. to the direction of motion.

if mass is halved, F = 100×(-2.5) = -250 N