Energy: Energy is the ability to do work or cause change. In an electrical circuit, power represents how quickly energy is being transferred.
Efficiency: Efficiency measures how effectively a device or system converts input energy into useful output energy. It is calculated by dividing the useful output power by the input power.
Series Circuit:A series circuit is a type of circuit where components are connected one after another along a single path. The same current flows through each component, and the total resistance equals the sum of individual resistances.