Torque : It is a measure of the force that can cause an object to rotate about an axis.

It is also known as moment or moment of force.

• As you can see the force F can be broken up into two components.
  • Fcosθ, which is parallel to the rod and cannot rotate the rod.
  • Fsin θ, which is perpendicular to the rod and contributes to the rotation.
• r is the radial distance from the axis of rotation to the point of application of the force
  • As the r is increased , the moment or torque produced increased.

                    Thus torque produced is

                    Where  ‘’ denotes the component of the force which is perpendicular to the radial distance (of rod)