Question

What is the moment of force developed about the hinge of a door if a person tries to open it with a force of 100 N, the force being applied normal to the door at handle which is at a distance of 60 cm from the hinge?

• A. 0 Nm
• B. 30 Nm
• C. 60 Nm
• D. Can’t say as angle is not specified

Answer 1

The correct option is C

60 Nm

We know that moment of a force about an axis is given by,

Moment of Force = Force $\times$ Perpendicular distance

As force is being applied normally, perpendicular distance, d = 60 cm = 0.6 m

T = F $\times$ d = 100 N $\times$ 0.6 m = 60 Nm