List of top Physics Questions on RC Circuits

A radioactive sample decays with an average life of 20 ms. A capacitor of capacitance 100 µF is charged to some potential. Then, the plates are connected through a resistance \(R\). What should be the value of \(R\) so that the ratio of the charge on the capacitor to the activity of the radioactive sample remains constant in time? Choose the correct answer.

The magnetic field at a point inside the 2.0 mH inductor coil becomes 0.80 of its maximum value in \(20\,\mu\text{s}\) when the inductor is joined to a battery. Then the resistance of the circuit is:

A capacitor of capacitance \(C\) is given a charge \(Q\). At \(t = 0\), it is connected to an uncharged capacitor of equal capacitance through a resistance \(R\). The charge on the second capacitor as a function of time is:

An ideal inductor, a resistor of resistance \(R\) Ohms and a capacitor with adjustable capacitance are connected in series to an alternating voltage with an effective value of \(V\) Volts and frequency of \(f\) Hz. The current flowing through the circuit when the capacitance of the capacitor is set to \(C_1\) is the same as when the capacitance of the capacitor is set to \(C_2\), \(C_2 > C_1\). The inductance of the inductor \(L\) is given by: