Question Detail
Question
A 10μF capacitor is charged by a 24V battery through a 400kΩ resistor. After 1s, what is the voltage across the resistor?
Correct Answer
Option D is the correct answer.
Detailed Explanation
Time constant RC = 400×10³×10×10⁻⁶ = 4s. V_capacitor(1s) = 24(1-e^(-1/4)) ≈ 5.3V, so V_resistor = 24 - 5.3 ≈ 18.7V.
Hint
Find the capacitor voltage using the charging equation V=V0(1-e^(-t/RC)), then subtract from the source voltage to get the resistor's voltage.