The wave equation y = 0.05 sin(20πx − 100πt) SI units. The wave speed is
A{'text': '0.5 m/s', 'label': 'A'}
B{'text': '100π m/s', 'label': 'B'}
C{'text': '20π m/s', 'label': 'C'}
D{'text': '5 m/s', 'label': 'D'}
Answer & Solution
Correct answer: D. {'text': '5 m/s', 'label': 'D'}
1. General form: y = A sin(kx − ωt) with k = 20π rad/m and ω = 100π rad/s.
2. Wave speed v = ω / k.
3. v = (100π) / (20π) = 5 m/s.
4. So the wave travels 5 m per second in the +x direction.
_Source: NCERT Class 11 Physics, Ch 14 "Waves", §14.3_
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