Solve.
-The power that a resistor must dissipate is jointly proportional to the square of the current flowing through the resistor and the resistance of the resistor. If a resistor needs to dissipate 75 watts of Power when 5 amperes of current is flowing through the resistor whose resistance is 3 ohms, find The power that a resistor needs to dissipate when 8 amperes of current are flowing through a
Resistor whose resistance is 3 ohms.
A) 192 watts
B) 72 watts
C) 24 watts
D) 120 watts

Question

Quizplus · Accepted Answer

The power dissipated by a resistor is given by the formula $P = I^2R$, where $P$ is the power in watts, $I$ is the current in amperes, and $R$ is the resistance in ohms. Given that a resistor dissipates 75 watts with 5 amperes and 3 ohms, we can confirm the formula works as $75 = 5^2 \times 3$. For 8 amperes and the same resistance of 3 ohms, the power dissipated is $P = 8^2 \times 3 = 64 \times 3 = 192$ watts.

Solve. -The Power That a Resistor Must Dissipate Is Jointly Proportional