JEE Main 2021 — Alternating Current Question with Solution
From: JEE Main 2021 (Online) 20th July Morning Shift
Question
In an LCR series circuit, an inductor 30 mH and a resistor 1 are connected to an AC source of angular frequency 300 rad/s. The value of capacitance for which, the current leads the voltage by 45 is F. Then the value of x is ____________.
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Show full solutionCorrect answer: 3
Correct answer
3
Step-by-step explanation
Given,
Inductance, L = 30 mH
Resistance, R = 1
Angular frequency, = 300 rad/s
We know that in L-C-R circuit,
where, = phase angle = 45
XC = capacitive reactance =
XL = inductive reactance = L
[ tan 45 = 1]
.... (i)
According to question, the value of capacitance is . So, on comparing it with Eq. (i), we can say x = 3.
Inductance, L = 30 mH
Resistance, R = 1
Angular frequency, = 300 rad/s
We know that in L-C-R circuit,
where, = phase angle = 45
XC = capacitive reactance =
XL = inductive reactance = L
[ tan 45 = 1]
.... (i)
According to question, the value of capacitance is . So, on comparing it with Eq. (i), we can say x = 3.
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