Torque due to action-reaction force is zero?
The torque due to an action-reaction force pair is not always zero. In fact, the torque due to the action-reaction force pair is usually not zero.
In physics, every action has an equal and opposite reaction. When two objects interact, they exert equal and opposite forces on each other. These forces are known as the action-reaction force pair.
Torque, on the other hand, is the rotational equivalent of force. It is the measure of the ability of a force to cause rotational motion around an axis. Torque is defined as the product of the force and the perpendicular distance from the axis of rotation to the line of action of the force.
When an action and reaction pair of forces act at different points on an object, they will generally result in a non-zero torque. This is because the perpendicular distances from the axis of rotation to the lines of action of the forces are not the same, resulting in a net torque.
However, there are certain scenarios where the torque due to an action-reaction force pair can be zero. One such scenario is when the two forces act along the same line but in opposite directions, and the perpendicular distances from the axis of rotation to the lines of action of the forces are equal. In this case, the torques due to the action and reaction forces cancel each other out, resulting in a net torque of zero.