Relation between Power, Force and Velocity - QS Study
QS Study

Relation between Power, Force and Velocity

Suppose force F is acting on a body for time t. If during this time the body moves along the direction of the applied force to a distance s, then work done by that force is, W = F x s

Again, power, P = W/t= = Fs/t = Fv … … … (1) [as we know, s = v/t]

So, power = applied force x velocity of the body

If the displacement of the body, instead of being along the force, is along a direction making an angle θ with the applied force, then

P = Fv cos θ

This equation represents a scalar product of two vector quantities.

According to vector notation, P = F.v. … … … (2)

This equation gives the relation between power, force and velocity.

Power, in case of rotational motion:

In case of rotational motion we know,

Work = torque x angular displacement

Power, P = W/t = (Torque x angular displacement) / time

So, Power, P = Torque x angular velocity.