7.11 Figure 7.21 shows a series LCR circuit connected to a variable frequency 230 V source. L = 5.0 H, C = 80μF, R = 40 Ω.

(a) Determine the source frequency which drives the circuit in resonance.

(b) Obtain the impedance of the circuit and the amplitude of current at the resonating frequency.

(c) Determine the rms potential drops across the three elements of the circuit. Show that the potential drop across the LC combination is zero at the resonating frequency.

A circuit is made up of resistance 3 Ω and inductance 0.01 H. An alternating emf of 100 V at 50 Hz is connected, then the phase difference between the current and the emf in the circuit is

A radioactive sample decays by 63% of its initial value in 10s. It would have decayed by 50% of its initial value in :-

A coil has resistance of 30 ohm and inductive reactance 20 ohm at 50 Hz frequency. If an ac source of 200 V, 100 Hz is connected across the coil, current in coil will be

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A capacitor having capacitance of 100 µF is charged with a potential difference of 12 V is connected to an inductor of inductance 10 mH. Find the maximum current through the inductor.