(a) Work done: Work done by a force acting on an object is equal to the magnitude of the force multiplied by the distance moved in the direction of the force.

(b) Energy: Energy of a body is defined as the capacity or ability of the body to do work.

(c) Mechanical energy: Mechanical energy includes kinetic energy and potential energy.

(d) Kinetic energy: The energy possessed by a body by virtue of its motion.

(e) Potential energy: The energy possessed by a body due to its position or configuration.

(f) Power: Power is defined as the rate of doing work or the rate of transfer of energy.

(g) Commercial unit of energy: The energy used in households, industries, and commercial establishment are usually expressed in kilowatt-hour.

1 kWh 1 unit = 3.6 × 10⁶ J