power is the measure of rate of change of energy in any circuit,then how the energy is changing in any circuit or how the change in energy happens in circuit?
thanks.
Keep the resistance of the circuit at constant value. And then within permissible limit change the value of either voltage or current, you ll be able to feel the change of power. The classic example is, lighting a bulb. Try to increase voltage given to the bulb, you will see more illumination..
And for a DC circuit, voltage and current might be constant but temperature of components likely isn't. The energy supplied by the source can take many non-electrical forms too.