Equation 18-23 applies to any circuit element: The amount of power that flows into or out of a circuit element is equal to the product of the current through the element multiplied by the voltage across the element. For a given voltage \(V\), each small amount of charge \(\Delta{q}\) that traverses the circuit element transfers the same amount of energy into or out of the element; the more charge that traverses the element per unit time and so the greater the current \(i\), the greater the rate of energy transfer \(P\).