MEDIUM
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IMPORTANT
Earn 100

LCR series circuit is connected to an ac source of voltage V=V sin ω t. Using phasor diagrams, obtain an expression for the impedance and the phase angle between the voltage and the current.

Important Questions on Alternating Current

EASY
12th Goa Board
IMPORTANT
 In an Indian laboratory, a circuit running on low AC voltage is connected to the AC mains through an electrical device .Name the electrical device
EASY
12th Goa Board
IMPORTANT
 In an Indian laboratory, a circuit running on low AC voltage is connected to the AC mains through an electrical device .If the electrical device is 100% efficient, state whether its input current will be greater or less than the output current.
HARD
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IMPORTANT
Show that the voltage and current are always in phase when a resistance is connected across an A.C. source. Draw the phasor diagram for it. To tune a radio over a frequency range of 800 kHz to 1200 kHz , inductance ‘L’ is kept constant  and the corresponding capacitance is varied from C1 to C2 . Compare C1  to C2 .
EASY
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IMPORTANT
What is the phase difference between the input and the output voltage in a transistor oscillator circuit?