Question

a car is moving with a constant velocity of 30 metre per second when brakes are applied it stops after 10 second find the work done by brakes if mass of the car 1000kg​

Answer 1

Explanation:

u = 30

t= 10

v =0

a = v-u/t

a= -3

${v}^{2} = {u}^{2} - 2as$

${u}^{2} = 2as$

$30 \times 30 = 2 \times 3 \times s$

s = 900/6 = 150 m

W = F. s

= ma s

= 1000 × -3 × 150

= - 750 KJ