Question

A 55 kg person riding a bike puts all her weight on each pedal when climbing a hill. The pedals rotate in a circle of radius 17 cm. What is the maximum torque she exerts?
125.2 mN
179 mN
42 mN
91.6 mN

Answer 1

her body weight exerts force = mg = 55*9.8= 539N ( the ques says each pedal )

torque = r * F

torque = 0.17 m * 539N

torque = 91.6 Newton.

Answer 2

Given:

Mass = 50 kg

Radius = 17 cm

To Find:

Maximum torque

Solution:

Force exerted by her body,

F = mg

F = 55 × 9.8

F = 539 N

Maximum torque = r × F

r = 17 cm = 0.17 m

Maximum torque = 0.17 × 539

Maximum torque = 91.6 Nm (Option 4)

The maximum torque she exerts is 91.6 mN.