A car approaching a crossing at a speed of 20 m/s sounds a horn of frequency 500Hz. when at 80m from the crossing, Speed of sound in air is 330 m/s. What freqnency is heard by an observer 60 m from the crossing on the straight road which crosses car road at right angles?

A car approaching a crossing at a speed of 20 m/s sounds a horn of fre

1.	A car approaching a crossing at a speed of 20 m/s sounds a horn of frequency 500Hz. when at 80m from the crossing, Speed of sound in air is 330 m/s. What freqnency is heard by an observer 60 m from the crossing on the straight road which crosses car road at right angles?
Answer» Solution :The situation is as SHOWN in figure. `cos theta =80/100 = 4/5` `:.` Apparent FREQUENCY is `f_("app") =(V/(v - v_s cos theta)) f = (330/(330 - 20 XX 4/5)) (500)` ` =525.5 HZ`

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A car approaching a crossing at a speed of 20 m/s sounds a horn of frequency 500Hz. when at 80m from the crossing, Speed of sound in air is 330 m/s. What freqnency is heard by an observer 60 m from the crossing on the straight road which crosses car road at right angles?

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