A radio tuner uses a series RLC circuit with resistance and inductance
PHYSICS · Multi-part · CBSE · Physics · Alternating Current · Alternating Current
Problem
A radio tuner uses a series RLC circuit with resistance R=15Ω and inductance L=2.5μH. It is connected to a constant-amplitude supply of 12V (rms).
(i) The circuit is first adjusted so that its resonant frequency is 1.0MHz. Calculate the peak current in this condition.
(ii) Keeping L unchanged, the capacitance is now increased so that the resonant frequency becomes 0.90MHz while the supply frequency remains at 1.0MHz. Determine the new peak current in the circuit.
(iii) Briefly explain, using numerical results obtained, why the current amplitude changes when the circuit is taken off resonance.