[amp_mcq option1=”P = I2R” option2=”P = IE” option3=”P = E2/R” option4=”I = P/E E. None of the above” correct=”option1″]
The correct answer is A. P = I2R.
Power is the rate at which energy is transferred or converted. In the case of a resistor, power is dissipated as heat. The amount of power dissipated is proportional to the square of the current through the resistor, and to the resistance of the resistor.
The equation $P = I^2R$ can be derived from Ohm’s law, which states that the voltage across a resistor is equal to the current through the resistor times the resistance of the resistor. In other words, $V = IR$. Substituting this into the equation for power, $P = IV$, we get $P = I^2R$.
Option B, $P = IE$, is incorrect because it does not take into account the resistance of the resistor. Option C, $P = E^2/R$, is incorrect because it does not take into account the current through the resistor. Option D, $I = P/E$, is incorrect because it does not take into account the resistance of the resistor. Option E, None of the above, is incorrect because the equation $P = I^2R$ is the correct equation for power dissipation in a resistor.