The amount of power wasted in heat is a function of efficiency. Any power that is not useful, such as signal power, is wasted in heat. In order to determine the amount of wasted power, the total input power must first be determined by using the power formula(see Reference Sheet):P = IE

Once the total input power is found, subtract the useful power from it. What is left is the power wasted in heat.

P = IE = 0.1 * 48 = 4.8 W

4.8 W – 1.5 W = 3.3 W of wasted power

The amount of power wasted in heat is a function of efficiency. Any power that is not useful, such as signal power, is wasted in heat. In order to determine the amount of wasted power, the total input power must first be determined by using the power formula(see Reference Sheet):P = IE

Once the total input power is found, subtract the useful power from it. What is left is the power wasted in heat.

P = IE = 0.1 * 48 = 4.8 W

4.8 W – 1.5 W = 3.3 W of wasted power