356240
In series \(L C R\) circuit at resonance, the phase difference between voltage and current is
1 \(\dfrac{\pi}{4}\)
2 \(\dfrac{\pi}{2}\)
3 zero
4 \(\pi\)
Explanation:
At resonance condition \(\phi=0\) between voltage and current. Correct option is (3).
KECT - 2023
PHXII07:ALTERNATING CURRENT
356241
For a series \(LCR\) circuit at resonance, the statement which is not true is
1 Wattless current is zero
2 Power factor is zero
3 Peak energy stored by a capacitor \( = \) peak energy stored by an inductor
4 Average power \( = \) apparent power
Explanation:
For a series \(LCR\) circuit at resonance, total reactance is zero and impedance is purely resistive. The phase angle \(\phi \) between the current and voltage is zero. Hence power factor \(\cos \phi = \cos 0^\circ = 1\) .Therefore statement (2) is wrong.
KCET - 2009
PHXII07:ALTERNATING CURRENT
356242
Which voltmeter will give zero reading at resonance?
1 \({V_2}\)
2 \({V_3}\)
3 \({V_1}\)
4 \({\rm{None}}\)
Explanation:
At resonance, the voltage across \(L\) and \(C\) are equal but opposite in phase. The reading of \({V_2}\) is zero
PHXII07:ALTERNATING CURRENT
356243
A \(LCR\) circuit is at resonance for a capacitor \(C\), inductance \(L\) and resistance \(R\). Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now
1 double
2 halved
3 zero
4 same
Explanation:
The impedance of \(LCR\) circuit is given by, \(Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}\) At resonance, \(X_{L}=X_{C}\) \(Z=R\) \(\therefore Z_{1}=R_{1}\) and \(Z_{2}=R_{2}\)
\(\Rightarrow I_{1}=\dfrac{V}{Z_{1}}=\dfrac{V}{R} ; \quad I_{2}=\dfrac{V}{Z_{2}}=\dfrac{2 V}{R}\) \(\therefore I_{2}=2 I_{1}\) Current amplitude will be double
356240
In series \(L C R\) circuit at resonance, the phase difference between voltage and current is
1 \(\dfrac{\pi}{4}\)
2 \(\dfrac{\pi}{2}\)
3 zero
4 \(\pi\)
Explanation:
At resonance condition \(\phi=0\) between voltage and current. Correct option is (3).
KECT - 2023
PHXII07:ALTERNATING CURRENT
356241
For a series \(LCR\) circuit at resonance, the statement which is not true is
1 Wattless current is zero
2 Power factor is zero
3 Peak energy stored by a capacitor \( = \) peak energy stored by an inductor
4 Average power \( = \) apparent power
Explanation:
For a series \(LCR\) circuit at resonance, total reactance is zero and impedance is purely resistive. The phase angle \(\phi \) between the current and voltage is zero. Hence power factor \(\cos \phi = \cos 0^\circ = 1\) .Therefore statement (2) is wrong.
KCET - 2009
PHXII07:ALTERNATING CURRENT
356242
Which voltmeter will give zero reading at resonance?
1 \({V_2}\)
2 \({V_3}\)
3 \({V_1}\)
4 \({\rm{None}}\)
Explanation:
At resonance, the voltage across \(L\) and \(C\) are equal but opposite in phase. The reading of \({V_2}\) is zero
PHXII07:ALTERNATING CURRENT
356243
A \(LCR\) circuit is at resonance for a capacitor \(C\), inductance \(L\) and resistance \(R\). Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now
1 double
2 halved
3 zero
4 same
Explanation:
The impedance of \(LCR\) circuit is given by, \(Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}\) At resonance, \(X_{L}=X_{C}\) \(Z=R\) \(\therefore Z_{1}=R_{1}\) and \(Z_{2}=R_{2}\)
\(\Rightarrow I_{1}=\dfrac{V}{Z_{1}}=\dfrac{V}{R} ; \quad I_{2}=\dfrac{V}{Z_{2}}=\dfrac{2 V}{R}\) \(\therefore I_{2}=2 I_{1}\) Current amplitude will be double
356240
In series \(L C R\) circuit at resonance, the phase difference between voltage and current is
1 \(\dfrac{\pi}{4}\)
2 \(\dfrac{\pi}{2}\)
3 zero
4 \(\pi\)
Explanation:
At resonance condition \(\phi=0\) between voltage and current. Correct option is (3).
KECT - 2023
PHXII07:ALTERNATING CURRENT
356241
For a series \(LCR\) circuit at resonance, the statement which is not true is
1 Wattless current is zero
2 Power factor is zero
3 Peak energy stored by a capacitor \( = \) peak energy stored by an inductor
4 Average power \( = \) apparent power
Explanation:
For a series \(LCR\) circuit at resonance, total reactance is zero and impedance is purely resistive. The phase angle \(\phi \) between the current and voltage is zero. Hence power factor \(\cos \phi = \cos 0^\circ = 1\) .Therefore statement (2) is wrong.
KCET - 2009
PHXII07:ALTERNATING CURRENT
356242
Which voltmeter will give zero reading at resonance?
1 \({V_2}\)
2 \({V_3}\)
3 \({V_1}\)
4 \({\rm{None}}\)
Explanation:
At resonance, the voltage across \(L\) and \(C\) are equal but opposite in phase. The reading of \({V_2}\) is zero
PHXII07:ALTERNATING CURRENT
356243
A \(LCR\) circuit is at resonance for a capacitor \(C\), inductance \(L\) and resistance \(R\). Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now
1 double
2 halved
3 zero
4 same
Explanation:
The impedance of \(LCR\) circuit is given by, \(Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}\) At resonance, \(X_{L}=X_{C}\) \(Z=R\) \(\therefore Z_{1}=R_{1}\) and \(Z_{2}=R_{2}\)
\(\Rightarrow I_{1}=\dfrac{V}{Z_{1}}=\dfrac{V}{R} ; \quad I_{2}=\dfrac{V}{Z_{2}}=\dfrac{2 V}{R}\) \(\therefore I_{2}=2 I_{1}\) Current amplitude will be double
356240
In series \(L C R\) circuit at resonance, the phase difference between voltage and current is
1 \(\dfrac{\pi}{4}\)
2 \(\dfrac{\pi}{2}\)
3 zero
4 \(\pi\)
Explanation:
At resonance condition \(\phi=0\) between voltage and current. Correct option is (3).
KECT - 2023
PHXII07:ALTERNATING CURRENT
356241
For a series \(LCR\) circuit at resonance, the statement which is not true is
1 Wattless current is zero
2 Power factor is zero
3 Peak energy stored by a capacitor \( = \) peak energy stored by an inductor
4 Average power \( = \) apparent power
Explanation:
For a series \(LCR\) circuit at resonance, total reactance is zero and impedance is purely resistive. The phase angle \(\phi \) between the current and voltage is zero. Hence power factor \(\cos \phi = \cos 0^\circ = 1\) .Therefore statement (2) is wrong.
KCET - 2009
PHXII07:ALTERNATING CURRENT
356242
Which voltmeter will give zero reading at resonance?
1 \({V_2}\)
2 \({V_3}\)
3 \({V_1}\)
4 \({\rm{None}}\)
Explanation:
At resonance, the voltage across \(L\) and \(C\) are equal but opposite in phase. The reading of \({V_2}\) is zero
PHXII07:ALTERNATING CURRENT
356243
A \(LCR\) circuit is at resonance for a capacitor \(C\), inductance \(L\) and resistance \(R\). Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now
1 double
2 halved
3 zero
4 same
Explanation:
The impedance of \(LCR\) circuit is given by, \(Z=\sqrt{R^{2}+\left(X_{L}-X_{C}\right)^{2}}\) At resonance, \(X_{L}=X_{C}\) \(Z=R\) \(\therefore Z_{1}=R_{1}\) and \(Z_{2}=R_{2}\)
\(\Rightarrow I_{1}=\dfrac{V}{Z_{1}}=\dfrac{V}{R} ; \quad I_{2}=\dfrac{V}{Z_{2}}=\dfrac{2 V}{R}\) \(\therefore I_{2}=2 I_{1}\) Current amplitude will be double
