Question

Define:
(i) Work
(ii) Energy
(iii) Power
Give their SI units.

Answer 1

(i) Work: Work is said to be done when a force creates a displacement in the direction of that force.
SI unit of work: joule $\left(\text{J}\right)$

(ii) Energy: The ability to do work is called energy.
SI unit of energy: joule $\left(\text{J}\right)$

(iii) Power: The rate of doing work is called power.
It is also defined as the rate of spending or obtaining energy.
SI unit of power: watt $\left(\text{W}\right)$