## Question

A source of sound vibrates according to the equation *y* = 0.05 cos π *t*. It sends waves of velocity 1.5 ms^{ –1}. The wavelength of the waves is ^{ }

### Solution

3.0 m

Angular frequency ω = π or 2 π *V* = π or *V* = 0.5 Hz. Now *v* = 1.5 ms^{ –1}. Therefore λ = *v*/*V* = 1.5/0.5 = 3m. ^{ }

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