Question 490: Waves

Question

Two stationary sources each emitting waves of wavelength $$\lambda $$, an observer moves from one source to another with velovcity u. Then number of beats heard by him

Accepted Answer

$$f' = {{v - u} \over v}f;f'' = {{v + u} \over v}f$$
Number of beats = $$f'' - f' = {{2u} \over \lambda }$$

Answer

$${{2u} \over \lambda }$$

Answer

$${u \over \lambda }$$

Answer

$$\sqrt {u\lambda } $$

Answer

$${u \over {2\lambda }}$$

Waves

Two stationary sources each emitting waves of wavelength $\lambda $, an observer moves from one source to another with velovcity u. Then number of beats heard by him

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