Question

Cyclist is pedalling his cycle at a constant velocity of 3 m/s . He applies brakes and stop the cycle in 6 s.

What is the average force of brakes if mass of cycle and the cyclist together is 80 kg?

a) 80 N. b) 8.0 N. c) 40 N d) 120 N​

Answer 1

u = 3 m/s

v = 0 m/s

t = 6 s

m = 80 kg

a = (v-u)/t

» a = -0.5 m/s²

F = ma

» F = 80 × 0.5

» F = 40 N

Option (c) ✓