Q15 of 51 Page 330

Consider the situation of the previous problem. Find the average electric field energy stored in the capacitor and the average magnetic field energy stored in the coil.

Given: resistance R = 300Ω,


Capacitance of capacitor C = 20 μF,


Inductance of inductor L = 1.0 Henry,


Voltage across the circuit ϵrms = 50 V and


Frequency v = 50/π Hz


Then the rms current across the circuit



Where Z is impedance in the circuit







Then,


Electric energy stored in capacitor will be





Magnetic field energy stored in the coil will be





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In a series LCR circuit with an AC source, R = 300Ω, C = 20 μF, L = 1.0 Henry, ϵrms = 50 V and v = 50/π Hz. Find

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(b) What is the value of this maximum current?


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An inductor-coil, a capacitor and an AC source of rms voltage 24 V are connected in series. When the frequency of the source is varied, a maximum rms current of 6.0 A is observed. If this inductor coil is connected to a battery of emf 12 V and internal resistance 4.0Ω, what will be the current?