Question

what is torque?how can it expressed in Kgm?

Answer 1

Torque is a measure of how much a force acting on an object causes that object to rotate.

Torque, also called moment or moment of force, is the tendency of a force to rotate an object about an axis, fulcrum, or pivot.

Just as a force is a push or a pull, a torque can be thought of as a twist.

Answer 2

The magnitude of torque depends on three quantities: the force applied, the length of the lever arm connecting the axis to the point of force application, and the angle between the force vector and the lever arm.

i.e. τ = r * F
τ is the magnitude of the torque,
r is the length (or magnitude) of the lever arm vector,
F is the magnitude of the force,

or τ = rFsinΘ
τ is the torque vector
r is the displacement vector
F is the force vector
θ is the angle between the force vector and the lever arm vector.

Answer 3

The SI unit for torque is the newton metre (N·m).

Non-SI units of torque includes "kilograms-metre-force"