JEE Mains · Physics · STD 11 - 14. waves and sound
A submarine \((A)\) travelling at \(18\, km/hr\) is being chased along the line of its velocity by another submarine \((B)\) travelling at \(27\, km/hr\). \(B\) sends a sonar signal of \(500\, Hz\) to detect \(A\) and receives a reflected sound of frequency \(v\). The value of \(v\) is close to ... \(Hz\) (Speed of sound in water \(= 1500\, ms^{-1}\))
- A \(499\)
- B \(502\)
- C \(504\)
- D \(507\)
Answer & Solution
Correct Answer
(B) \(502\)
Step-by-step Solution
Detailed explanation
\(v =\) speed of sound in water \(=1500 m / s\) frequency received by \(A = f\) \(=\left[\frac{ V - V _{ A }}{ V - V _{ B }}\right] f _{0}=\left[\frac{1500-5}{1500-7.5}\right] f _{0}\) frequency received by \(B = f ^{\prime \prime}=\)…
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