Alternating Current

Physics
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In series L-C-R resonant circuit, to increase the resonant frequency :

A
L will have to be increased
B
C will have to be increased
C
LC will have to be decreased
D
LC will have to be increased
Medium
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At low frequency a condenser offers :

A
high impedance
B
low impedance
C
zero impedance
D
impedance of condenser is independent of frequency
Medium
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If in a series L-C-R ac circuit, the voltages across R, L, C are respectively. Then the voltage of applied AC source is always equal to :

A
B
C
D
Medium
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If the frequency of an alternating e.m.f. is f in L-C-R circuit, then the value of impedance Z as log(frequency) increases :

A
increases
B
increases and then becomes equal to resistance, then it will start decreasing
C
decreases and when it becomes minimum, equal to the resistance then it will start increasing
D
go on decreasing
Medium
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An inductance and resistance are connected in series with an A.C circuit. In this circuit

A
the current and P.d. across the resistance lead P.d across the inductance by
B
the current and P.d across the resistance lags behind the P.d. across the inductance by angle 
C
The current across resistance leads and the P.d across resistance lags behind the P.d across the inductance by
D
the current across resistance lags behind and the P.d across the resistance leads the P.d across the inductance by
Medium
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If a capacitor is connected to two different A.C. generators, then the value of capacitive reactance is:

A
directly proportional to frequency
B
inversely proportional to frequency
C
independent of frequency
D
inversely proportional to the square of frequency
Medium
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Ratio of impedance to capacitive reactance has

A
no units
B
ohm
C
ampere
D
tesla
Medium
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