Question

Q. 2] Answer the following (Each 1 Mark)
1) What are the dimensions of power?​

Answer 1

Answer:

Common symbols

P

SI unit

watt (W)

In SI base units

kg⋅m2⋅s−3

Derivations from

other quantities

P = E/t

P = F·v

P = V·I

P = τ·ω

Dimension

{\displaystyle {\mathsf {L}}^{2}{\mathsf {M}}{\mathsf {T}}^{-3}}{\displaystyle {\mathsf {L}}^{2}{\mathsf {M}}{\mathsf {T}}^{-3}}

Explanation:

The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. The power involved in moving a ground vehicle is the product of the traction force on the wheels and the velocity of the vehicle. In classical mechanics, as quantified from a stationary frame of reference, the motive power of a jet-propelled vehicle is the product of the engine thrust and the velocity of the vehicle (note that by this definition, a propelled vehicle hovering at stationary elevation over a gravitational body, where the upward thrust exactly cancels the downward acceleration of gravity, the motive power is zero). The rate at which a light bulb converts electrical energy into light and heat is measured in watts – the electrical energy used per unit of time.[4][5]