Question

Question #10: What is the basic character for RC circuit? In other words, how do the current and voltage change with time? What about the discharging? What is the time constant? How to compute it? How to compute the time constant. How does the charge capacitor change with respect to time?

Answer 1

The voltage and current change exponentially with time and becomes constant after a certain point.

Same is true for discharging but here the values decrease.

Time constant is the time required to charge the capacitor, through the resistor, from an initial charge voltage of zero to ≈63.2 percent of the value of an applied DC voltage, or to discharge the capacitor through the same resistor to ≈36.8 percent of its initial charge voltage.

The RC time constant, also called tau, the time constant of an RC circuit, is equal to the product of the circuit resistance and the circuit capacitance. SO we compute it by simply multiplying R and C.

he capacitor is fully charged when Vc = Vs. Vc increases as soon as charge (Q) starts to build up (Vc = Q/C), This reduces the voltage across the resistor and therefore reduces the charging current. This means that the rate of charging becomes progressively slower