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Question
Calculate the quality factor of a series LCR circuit with L = 2.0 H, C = 2μF and R = 10 Ω. Mention the significance of quality factor in LCR circuit.
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Solution
Given,
L = 2.0 H
C = 2μF = 2 × 10−6 F
R = 10 Ω
Now,Q-fector `= 1/R sqrtL/C`
`=1/10sqrt(2/(2 xx 10^-6))`
`= 1/(10 xx 10^-3) = 1/10^-2 =100`
Quality factor is also defined as
`Q =2pi f xx text{Energy Stored}/text{Power loss}`
So higher the value of Q means the energy loss is at lower rate relative to energy stored i.e. the oscillations will die slowly and damping would be less.
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