Superposition is a powerful tool that allows us to solve for current and voltage in linear circuits containing several by adding component current and voltage. In general, superposition will not work in nonlinear circuits. Its validity is also limited, even in linear circuit, to calculation of current and voltage. In particular, the total power dissipated by an element in a linear circuit is not in general the sum of separate powers due to each source. This is because power is nonlinear function of the circuit variables current and voltage. The use of superposition is limited to calculating current and voltage in linear circuit.