Question 178: Waves

Question

A stationary source emits sound waves of
frequency 500 Hz. Two observers moving
along a line passing through the source detect
sound to be of frequencies 480 Hz and 530 Hz.
Their respective speeds are, in ms–1,
(Given speed of sound = 300 m/s)

Accepted Answer

$$v = {{v + {v_o}} \over v}{v_o}$$
$$ \Rightarrow {v_o} = \left( {{v \over {{v_o}}} - 1} \right)v$$
$${v_o} = \left( {{{530} \over {500}} - 1} \right)300 = 18\,m/s$$
$${v_o} = \left| {\left( {{{480} \over {500}} - 1} \right)300} \right| = 12\,m/s$$

Answer

12, 18

Answer

16, 14

Answer

12, 16

Answer

8, 18

Waves

A stationary source emits sound waves of frequency 500 Hz. Two observers moving along a line passing through the source detect sound to be of frequencies 480 Hz and 530 Hz. Their respective speeds are, in ms–1, (Given speed of sound = 300 m/s)

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