Define the following terms: (i) Work (ii) Potential difference (iii) Power – NABTEB QUESTION

Define the following terms:
(i) Work
(ii) Potential difference
(iii) Power

Work is said to be done when a force moves through a distance in the direction of the force. Work is measured in joules(J) or Newton-metres (Nm) and it is symbolized by letter W or E.

Potential difference (p.d) is defined as the voltage measured across a circuit when an electric current is flowing or in a closed circuit. It is also called on-load voltage or closed circuit voltage. Potential difference can also be defined as the voltage measured between two points when an electric current is
flowing. p.d is denoted by the symbol V and it is measured in volts.

The term power is defined as the ratio at which work is said to be done. But, electric power is the rate at which any device or appliance consumes electric current in a closed (d.c) circuit. It is represented by P and measured in watts(W)