Assertion :If the frequency of the applied AC is doubled, then the power factor of a series $R - L$ circuit decreases. Reason: Power factor of series $R - L$ circuit is given by $cos θ = \frac{2 R}{\sqrt{R^{2} + ω^{2} L^{2}}}$

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Assertion is correct but Reason is incorrect

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Both Assertion and Reason are incorrect

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C Assertion is correct but Reason is incorrect
The impedance in circuit due to inductor $= ω L; ω = 2 π f$
The impedance due to resistor $= R$
Hence the overall impedance of the circuit $= \sqrt{R^{2} + ω^{2} L^{2}}$
Thus the power factor is given as $c o s θ = \frac{R}{\sqrt{R^{2} + ω^{2} L^{2}}}$
Thus as the frequency of applied AC is doubled, the power factor of the circuit decreases.

Suggest Corrections

Similar questions

Q. Assertion: The compressibility factor for

H_{2}

and

H e

(1 + \frac{P b}{R T})

Reason: The compressibility factor for

H_{2}

and

H e

can be derived from Van der Waal's equation.

ASSERTION: n-Pentane and n-Hexane belong to a homologous series.

REASON: n-Pentane and n-Hexane belong to the same class of hydrocarbons and they differ by a - $C H_{2}$ - group.

Assertion (A) Order and molecularity are same.

Reason (R) Order is determined experimentally and molecularity is the sum of the stoichimetric coeffcient of rate determining elementary step.

(a) Both assertion and reason are correct and the reason is correct explanation of assertion
(b) Both assertion and reason are correct, but reason does not explain assertion.
(c) Assertion is correct, but reason is incorrect
(d) Both assertion and reason are incorrect
(e) Assertion is incorrect but reason is correct.

Assertion (A) Order of the reaction can be zero or fractional.

Reason (R) We cannot determine order from balanced chemical equation.

Q. Assertion [A]: Deforestation is one of the main factors contributing to global warming.
Reason [R]: Besides

C O_{2}

, methane and CFCs are also greenhouse gases.

Join BYJU'S Learning Program

Assertion :If the frequency of the applied AC is doubled, then the power factor of a series R−L circuit decreases. Reason: Power factor of series R−L circuit is given by cosθ=2R√R2+ω2L2

Assertion :If the frequency of the applied AC is doubled, then the power factor of a series $R - L$ circuit decreases. Reason: Power factor of series $R - L$ circuit is given by $cos θ = \frac{2 R}{\sqrt{R^{2} + ω^{2} L^{2}}}$