If a 1 µF capacitor and a 10 kΩ resistor are connected in series across 20 VDC, approximately how much voltage will the capacitor drop after charging for just one time constant?
A)12.6 V
B)11.0 V
C)17 V
D)12.1 V

Question

Quizplus · Accepted Answer

After one time constant (τ = RC), the voltage across the capacitor is approximately 63.2% of the supply voltage. Therefore, the voltage drop is 20V * (1 - 0.632) = 7.36V, so the remaining voltage is approximately 12.6V.

If a 1 µF Capacitor and a 10 KΩ Resistor