Question

20] 4 car is speeding along a level road at 25 m/s. The brakes bring the 500 kg car to a speed of 3
m/s over a distance of 5 m. Determine the force by brakes and work done on the car by brakes​

Answer 1

initial velocity = 25m/s

final velocity = 3m/s

mass of car = 500 kg

distance = 5m

V² - u² = 2 a s

3² - 25² = 2 a 5m

9 - 625 = 10a

625 - 9 = 10a

root of 616

24.8 =10a

a = 2.48m/s²

F = MA

F = 500(2.48)

F = 1240N