Torque:

The torque characterises the rotational effect of a pair of forces on a rotatable system.

The absolute value of the torque M is calculated from the absolute value of a forceF and the length of the appendant lever arm of the force a.

M	Torque
F	Absolute value of a force which operates on the lever
a	arm of the lever (distance between the line of application of the force and the centre of rotation D)