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JEE Main202120 Jul 2021Morning ShiftPhysicsAlternating CurrentActual

In an L C R series circuit, an inductor 30 mH and a resistor 1 Ω are connected to an AC source of angular frequency 300 rad s - 1 . The value of capacitance for which the current leads the voltage by 45 ° is 1 x × 10 - 3 F . Then the value of x is

Correct answer

0

Step-by-step solution

tan ϕ = x C - x L R tan 45 = x C - x L R x C - x L = R 1 ω C - ω L = R 1 ω C - 300 × 0 . 03 = 1 1 ω C = 10 C = 1 10 ω = 1 10 × 300 C = 1 3 × 10 - 3 X = 3

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