The amplitude of a wave is doubled. By what factor does its intensity change?
Answer and explanation
Correct answer: A. It increases by a factor of 4
- Step 1: Intensity is proportional to the amplitude squared. Step 2. Doubling the amplitude gives times the intensity. Answer: It increases by a factor of 4. Why not the others: doubling would apply if intensity were proportional to amplitude; 8 would be a cubic relationship; amplitude does affect intensity.
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