An alternating voltage e=200 text sin text 100t is applied to a series combination R=30 Ω and an inductor of 400 mH . The power factor of the circuit is

Question

An alternating voltage e=200 text sin text 100t is applied to a series combination R=30 Ω and an inductor of 400 mH . The power factor of the circuit is (A) 0.01 (B) 0.2 (C) 0.05 (D) 0.042

Tardigrade Admin · Accepted Answer

Power factor cos φ =(R/√R2+ω 2L2) =(30/√(30)2+(100)2× (400× 10-3)2) =(30/√900+1600)=(30/50)=0.6

Q. An alternating voltage $e = 200 s in 100 t$ is applied to a series combination $R = 30 Ω$ and an inductor of $400 m H$ . The power factor of the circuit is

0.01

0.2

0.05

0.042

0.6

Power factor $cos ϕ = \frac{R}{R ^{2} + ω ^{2} L ^{2}}$
$= \frac{30}{( 30 ) ^{2} + ( 100 ) ^{2} \times ( 400 \times 10 ^{- 3} ) ^{2}}$
$= \frac{30}{900 + 1600} = \frac{30}{50} = 0.6$

Q. An alternating voltage e=200sin100t is applied to a series combination R=30Ω and an inductor of 400mH . The power factor of the circuit is

0.01

0.2

0.05

0.042

0.6

Power factor cosϕ=R2+ω2L2​R​ =(30)2+(100)2×(400×10−3)2​30​ =900+1600​30​=5030​=0.6

Q. An alternating voltage $e = 200 s in 100 t$ is applied to a series combination $R = 30 Ω$ and an inductor of $400 m H$ . The power factor of the circuit is

Power factor $cos ϕ = \frac{R}{R ^{2} + ω ^{2} L ^{2}}$
$= \frac{30}{( 30 ) ^{2} + ( 100 ) ^{2} \times ( 400 \times 10 ^{- 3} ) ^{2}}$
$= \frac{30}{900 + 1600} = \frac{30}{50} = 0.6$