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Standard XII

Physics

Displacement Current

An electric l...

Question

An electric lamp which runs at $100 V$ dc and consumes $10 A$ current is connected to ac mains at $150 V, 50 H z$ cycles with a choke coil in series. The inductance of voltage across the choke is given as $x \times 10^{- 3} H$ .Find $x$ Neglect the resistance of choke.

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Solution

$V_{L} = \sqrt{V^{2} - V_{R}^{2}}$
$= \sqrt{(150)^{2} - (100)^{2}}$
$= 111.8 V$
$V_{L} = I X_{L} = I (2 π f L)$
$∴ L = \frac{V_{L}}{2 π f I} = \frac{111.8}{2 π \times 50 \times 10}$
$= 0.036 H$

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An electric lamp which runs at 100V dc and consumes 10A current is connected to ac mains at 150V,50Hz cycles with a choke coil in series. The inductance of voltage across the choke is given as x×10−3H.Find x Neglect the resistance of choke.

VL=√V2−V2R=√(150)2−(100)2=111.8VVL=IXL=I(2πfL)∴L=VL2πfI=111.82π×50×10=0.036H

An electric lamp which runs at $100 V$ dc and consumes $10 A$ current is connected to ac mains at $150 V, 50 H z$ cycles with a choke coil in series. The inductance of voltage across the choke is given as $x \times 10^{- 3} H$ .Find $x$ Neglect the resistance of choke.

$V_{L} = \sqrt{V^{2} - V_{R}^{2}}$
$= \sqrt{(150)^{2} - (100)^{2}}$
$= 111.8 V$
$V_{L} = I X_{L} = I (2 π f L)$
$∴ L = \frac{V_{L}}{2 π f I} = \frac{111.8}{2 π \times 50 \times 10}$
$= 0.036 H$