Question

A particular RC circuit is assembled from a 12 volt battery, a 300 Ω resistor, and a 73 µF capacitor. How long will it take the capacitor to achieve a charge of 63% of its maximum charge (once turned on)?

Answer 1

Answer:

$\tau = 0.0219$

Explanation:

The time $\tau$ it takes for the voltage across the capacitor $V_c$ to go from 0 volts to 63% of the source voltage is given by the formula:

$\tau= RC$

Where:

$\tau=Time\hspace{3}constant\\R=Electrical\hspace{3}resistance\\C=Capacitance$

After $5 \tau$ the voltage has risen to 99% of its final value.

Therefore:

$\tau =RC=300(73\times 10^{-6})=0.0219$