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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

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

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प्रश्न

For an LCR circuit, the power transferred from the driving source to the driven oscillator is P = I2Z cos φ.

  1. Here, the power factor cos φ ≥ 0, P ≥ 0.
  2. The driving force can give no energy to the oscillator (P = 0) in some cases.
  3. The driving force cannot syphon out (P < 0) the energy out of oscillator.
  4. The driving force can take away energy out of the oscillator.

विकल्प

  • a, b and c

  • a, b and d

  • b, c and d

  • c and d

MCQ
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उत्तर

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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अध्याय 7: Alternating Current - MCQ I [पृष्ठ ४२]

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एनसीईआरटी एक्झांप्लर Physics Exemplar [English] Class 12
अध्याय 7 Alternating Current
MCQ I | Q 7.11 | पृष्ठ ४२

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