A rigid body consists of ‘n’ particles of mass m1, m2, m3,……The body rotates about an axis with an angular velocity ω1, ω2, ω3……..

Question

The handle of a door is always found at one edge of the door which is located at a maximum possible distance away from hinges.

1. Give reason for it.

2. In which direction will the torque act while the door opens inside the room?

3. If the door handle is fixed at the middle of the door, what difference do you feel in the applied force to open the door.

Answer 1

1. Torque τ = r F sin θ

From the above equation it is clear that, we get maximum torque when the handle of a door is located at a maximum possible distance (r) away from hinge.

2. The direction of torque is always along the axis of rotation of door.

3. If the door handle is fixed at middle, more force must be applied to get maximum torque that is required to open the door.