Question

Define instantaneous power and also derive it​

Answer 1

Power: The rate of doing work or the amount of energy transferred is called power. The unit of power is joule per second .

The physical quantity obtained by dot product of force and velocity is Power. It is Scalar quantity.

Proof:

F.v = F.d/t  

Which implies,

W/t = P

Where,  

F - Force

v - Velocity

p=F.v

As power has no direction and is one dimensional measurement. So, it is regarded as a scalar quantity.