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STATEMENT-1: By only knowing the power f...

STATEMENT-1: By only knowing the power factor for a given LCR circuit it is not possible to tell whether the applied alternating emf leads or lags the current.
STATEMENT-2: `cos theta=cos(-theta)`

A

If both the assertion and reason are true and reason is a true explantion of the assertion.

B

If both the assertion and reason are true but the reason is not true the correct explantion of the assertion.

C

If the assertion is true but reason false

D

If both the assertion and reason are false.

Text Solution

Verified by Experts

The correct Answer is:
A
For a certain values of `cos theta` (power factor) two values of `theta` are possible. One is positive the other is much negative. Accordingly the applied e.m.f may lead or lag.
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STATEMENT-1: AC source is connected across a circuit. Power dissipated in circuit is P . The power is dissipated only across resistance. STATEMENT-2: Inductor and capacitor will not consume any power in AC circuit.

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Knowledge Check

  • STATEMENT - 1 : In a series L-C-R circuit, it is found that voltage leads current. When the capacitance of the circuit is increased, the power consumption will increase. and STATEMENT - 2 : The average power consumption at resonance is independent of inductor of capacitor.

    A
    Statement-1 is True, Statement-2, is True, Statement-2 is a correct explanation for Statement-8
    B
    Statement-1 is True, Statement-2, is True, Statement-2 is NOT a correct explanation for Statement-8
    C
    Statement-1 is True, Statement-2 is False
    D
    Statement-1 is False, Statement-2 is True

  • STATEMENT-1: In a series LCR circuit at resonance, the voltage across the capacitor or inductor may be more than the applied voltage. STATEMENT-2: At resonance in a series LCR circuit, the voltages across inductor and capacitor are out of phase.

    A
    Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.
    B
    Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1.
    C
    Statement-1 is True, Statement-2 is False.
    D
    Statement-1 is False, Statement-2 is True.

  • STATEMENT-1: AC source is connected across a circuit. Power dissipated in circuit is P . The power is dissipated only across resistance. STATEMENT-2: Inductor and capacitor will not consume any power in AC circuit.

    A
    Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.
    B
    Statement-1 is True, Statement-2 is True, Statement-2 is NOT a correct explanation for Statement-1.
    C
    Statement-1 is True, Statement-2 is False.
    D
    Statement-1 is False, Statement-2 is True.
    • A2Z-ALTERNATING CURRENT-Section B - Assertion Reasoning
    1. STATEMENT-1: By only knowing the power factor for a given LCR circuit ...

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    2. Statement 1: In the purely resistive element of a series LCR, ac circu...

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    3. Statement 1: In a series LCR circuit at resonance condition power cons...

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    4. Assertion: In series L-R circuit voltage leads the current. Reason: ...

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    5. Assertion: Average value of AC over a complete cycle is always zero. ...

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    6. Assertion: KVL rule is also being applied in AC circuit shown below. ...

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    7. Assertion: AC generators are based upon EMI principle. Reason: Resis...

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    8. Assertion: Rate of heat generated when resistance is connected with AC...

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    9. An inductor, a capacitor, and a resistor are connected in series. The ...

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    10. Asserition: In alternating current direction of motion free electron c...

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    11. Assertion: When frequency is greater than resonace frequency is a seri...

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    12. Assertion: When capacitive reactance is smaler than the inductive reac...

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    13. Statement 1: An alternating current shown magnetic effect. Statemen...

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    14. Assertion: The alternating current lags behined the e.m.f. by a phase ...

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    15. Assertion: Capacitance serves as a block for DC and offers an easy pat...

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    16. Assertion: When capacitive reactance is smaler than the inductive reac...

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    17. Assertion: Chock coil is the prefered over a resistor to adjust curren...

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    18. Statement 1: An alternating current shown magnetic effect. Statemen...

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    19. Statement 1: Both dc and ac can be measured by a hot wire instrument. ...

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    20. Assertion: AC is more dangerous than DC Reason: Frequency of AC is ...

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