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Question 31311
JEE Physics · Hard

Waves on String: Power in Waves MCQ

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Power in WavesHardQuestion 31311

Question

Power of wave on string is P. If amplitude doubles and frequency halves (with same tension):
  1. A
    P/4
  2. B
    P
    Correct
  3. C
    4P
  4. D
    2P

Correct answer

P

Explanation

P ∝ ω²A² = (2πf)²A². If f → f/2: ω → ω/2. If A → 2A: A² → 4A². P ∝ (ω/2)²×(2A)² = (ω²/4)×4A² = ω²A². Power unchanged.

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