Resistors of values 8.0 W,12.0 W,and 24.0 W are connected in series across a battery with a small internal resistance.Which resistor dissipates the greatest power?
A)the 8.0-W resistor
B)the 12.0-W resistor
C)the 24.0-W resistor
D)The answer depends on the internal resistance of the battery.

Question

Quizplus · Accepted Answer

The power dissipated by a resistor in a series circuit is given by P = V^2/R, where V is the voltage across the resistor and R is its resistance. In a series circuit, the same current flows through each resistor, but the voltage across each resistor depends on its resistance. Since the voltage drop across the series combination of resistors is equal to the battery voltage, the largest voltage drop will occur across the largest resistor. Therefore, the 24.0-W resistor will dissipate the greatest power, followed by the 12.0-W resistor and then the 8.0-W resistor.

Resistors of Values 8