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Question
For an LCR circuit, the power transferred from the driving source to the driven oscillator is P = I2Z cos φ.
- Here, the power factor cos φ ≥ 0, P ≥ 0.
- The driving force can give no energy to the oscillator (P = 0) in some cases.
- The driving force cannot syphon out (P < 0) the energy out of oscillator.
- The driving force can take away energy out of the oscillator.
Options
a, b and c
a, b and d
b, c and d
c and d
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Solution
a, b and c
Explanation:
As per question P = I2Z cos `phi`P = I2Z cos `phi`
Power factor cos `phi` = RZ cos `phi` = RZ
As R > 0 and Z > 0
So cos `phi` = RZ cos `phi` = RZ is positive ⇒ P > 0
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