WBJEE · Physics · Waves and Sound
The equation of a progressive wave is \(y=4 \sin (4 \pi t-0.04 x+\pi / 3)\) where \(x\) is in meter and \(t\) is in second. The velocity of the wave is
- A \(100 \pi \mathrm{m} / \mathrm{s}\)
- B \(50 \pi \mathrm{m} / \mathrm{s}\)
- C \(25 \pi \mathrm{m} / \mathrm{s}\)
- D \(\pi \mathrm{m} / \mathrm{s}\)
Answer & Solution
Correct Answer
(A) \(100 \pi \mathrm{m} / \mathrm{s}\)
Step-by-step Solution
Detailed explanation
Hints : Velocity of wave \(=\frac{\omega}{\mathrm{K}}=\frac{4 \pi}{0.04}=100 \pi \mathrm{m} / \mathrm{sec}\)
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