Question 520: Waves

Question

An observer moves towards a stationary source of sound with a speed 1/5th of the speed of sound. The wavelength and frequency of the source emitted are $$\lambda $$ and $$f$$ respectively. The apparent frequency and wavelength recorded by the observer are respectively

Accepted Answer

Apparent frequency, $$f' = {{v + {v_0}} \over v}f$$
$$ = {{v + (1/5)v} \over v}f = 1.2f$$
Wavelength does not change by motion of observer.

Answer

1.2 $$f$$,   1.2 $$\lambda $$

Answer

1.2 $$f$$,  $$\lambda $$

Answer

$$f$$,  1.2 $$\lambda $$

Answer

0.8 $$f$$,   0.8 $$\lambda $$

Waves

An observer moves towards a stationary source of sound with a speed 1/5th of the speed of sound. The wavelength and frequency of the source emitted are $\lambda and f$ respectively. The apparent frequency and wavelength recorded by the observer are respectively

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