Question

A car of 500kg mass is moving at velocity of 36km/hr is brought to rest over a distance of 40m. Now calculate the force required to stop the car. *​

Answer 1

Explanation:

A car of mass 500kg traveling at 36km/hr is brought to rest over a distance of 40km. What is the average retardation on average breaking force?

Data supplied: mass of car = 500 kg; initial speed = 36 km/h. traveled distance = 40 km

I am presuming that the braking distance is not 40 km because that is a very unrealistic value. I think this distance traveled after stepping on the brakes is only 40 m to make the situation realistic. To solve for the average retardation this formula is to be used. d = (final speed ^2- initial speed^2) / 2a where d = 40 m, final speed = 0; initial speed = 36 km/h and a is the average retardation.

36 km/h = 10 m/s.

Solving for the average retardation a

30 m = (0^2 - 10^2) / 2a

30 m = (0 - 100) / 2a

30 m = -100 /2a

2a = -100/30

2a = - -3.33

a = -1.67 m/s^2

The average retardation on average breaking force is -1.67 m/s^2.