Question

The mass of a minibus with the driver is 1.50×10^3 kg.Assume that the passengers have an average mass of 50.0kg each.The driver is moving at a speed of 30.0m.s^-1 when he notices that the traffic lights ahead have turned to red.He applies a force of 9000N on the brake pedal.
a)how far must he have been from the traffic lights if he were able to stop in time?
b)how long will it take him to stop?
c)how will the stopping distance change if the minibus is carrying 10 passengers

Answer 1

a) a = F/m = 9000/1500
x = v^2/(2*a)
b) t = v/a
c) Add 500 to mass in part a & repeat

Answer 2

how long it will take him to stop