(a) Define mechanical power and state its SI unit. (b) A body is pulled along a…

PHYSICS · Subjective · CBSE · Physics · Work, Energy and Power · Work, Energy and Power

Problem

(a) Define mechanical power and state its SI unit. (b) A body is pulled along a straight, horizontal surface by a constant force

F

and moves with a uniform velocity

v

. Starting only from the definition of power as the rate of doing work, derive an expression that relates

P

F

and

v

. (c) Mention one practical situation in everyday life where the expression obtained in part (b) is more convenient to use than the basic definition

P = W/t