A person observes two moving trains, '\(A\)' reaching the station and '\(B\)' leaving the station with equal speed of \(30\,m / s\). If both trains emit sounds with frequency \(300\,Hz\), (Speed of sound : \(330\,m / s\) ) approximate difference of frequencies heard by the person will be \(..........Hz\)

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Answer & Solution

Correct Answer

(B) \(55\)

Step-by-step Solution

Detailed explanation

\(f _1=300\left(\frac{330-0}{330-(-30)}\right)=275\)

\(f _2=300\left(\frac{330-0}{330-(30)}\right)=330\)

\(\Delta f =330-275=55\,Hz\)

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