If the values of C1 and R1 shown in the illustration were 1 microfarad and 3 megohms respectively, which of the listed intervals of time would equal one 'time constant'? EL-0086

Correct Answer: Option A — 3 seconds

The time constant of a resistor-capacitor (RC) circuit is the product of resistance and capacitance. Multiplying 3 megohms (3,000,000 ohms) by 1 microfarad (0.000001 farads) equals exactly 3 seconds, representing the time required to charge the capacitor to 63.2% of its capacity.