How long will it take to completely discharge a 0.47 $\mu \mathrm { F }$ capacitor through a 10 $\mathrm { k } \Omega$ resistor?
A) 0.47 ms
B) 23.5 ms
C) 2.35 s
D) 0.18 ms

Question

How long will it take to completely discharge a  0.47  $\mu \mathrm { F }$ capacitor through a 10 $\mathrm { k } \Omega$ resistor?
A)  0.47 ms
B)  23.5 ms
C)  2.35 s
D)  0.18 ms

Quizplus · Accepted Answer

The time constant $\tau$ for an RC circuit is given by $\tau = RC$, where $R$ is the resistance in ohms and $C$ is the capacitance in farads. For a 0.47 $\mu \mathrm { F }$ capacitor and a 10 $\mathrm { k } \Omega$ resistor, $\tau = 10,000 \Omega \times 0.47 \times 10^{-6} \mathrm { F } = 4.7 \times 10^{-3} \mathrm { s }$ or 4.7 ms. However, to completely discharge, it typically takes around 5 $\tau$, which is $5 \times 4.7 \mathrm { ms } = 23.5 \mathrm { ms }$.

How Long Will It Take to Completely Discharge a μF\mu \mathrm { F }μF

How Long Will It Take to Completely Discharge a $\mu \mathrm { F }$