Question

Define electric energy, electric power and write their SI units and commercial units.

Answer 1

Electric energy:

1. The energy is generated by the movement of electrons from one point to another.
2. The joule or watt-second is the fundamental unit of electrical energy.
3. A joule is defined as one ampere of current flowing through a circuit for one second when a potential difference of one volt is applied across it.
4. The kilowatt-hour (kWh), also known as the Board of Trade unit, is the commercial unit of electrical energy (B.O.T).
5. $1\mathrm{kwh}=1000\times 60\times 60$ watt-second $1\mathrm{kwh}=3.6\times {10}^6\mathrm{Ws}$or Joules. Generally, one kWh is called one unit.

Electric power:

1. Electrical power is defined as the rate at which an electrical circuit transfers electrical energy per unit of time. Electrical energy can be either kinetic or potential energy in this context.
2. In most cases, potential energy is taken into account, which is the energy stored as a result of the relative positions of charged particles or electric fields. P denotes electrical power, which is measured in Watts.
3. SI Unit is Watt, joule per second and Formula, P=VI Where, V is the potential difference (volts), I is the electric current.