what is torque

Torque is a measure of the force that can cause an object to rotate about an axis. It is the rotational analogue of linear force and is also referred to as the moment of force. Torque is a vector quantity, and its direction depends on the direction of the force on the axis. Torque is defined as the product of the magnitude of the perpendicular component of the force and the distance of the line of action of a force from the point around which it is being determined. Torque is measured in units of newton-meters (N⋅m) in the SI system, but it can also be expressed in other units such as pound-force-feet, lbf⋅inch, or ozf⋅in. Torque is present in everyday happenings, such as operating a doorknob, opening a soda bottle, using a wrench, or pedaling a bicycle. It is what causes an object to acquire angular acceleration, just as force causes an object to accelerate in linear kinematics.