JEE Mains · Physics · STD 11 - Waves and sound
- JEE Mains 2021
- Hard
- Numerical
A tuning fork \(A\) of unknown frequency produces \(5\, beats/s\) with a fork of known frequency \(340\, Hz\). When fork \(A\) is filed, the beat frequency decreases to \(2\, beats/s.\) What is the frequency of fork \(A\) ? (in \(Hz\))
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(335\)
Step-by-step Solution
Detailed explanation
Initially beat frequency \(=5 \,Hz\)
so, \(\rho_{ A }=340 \pm 5=345\, Hz ,\) or \(335\, Hz\)
after filing frequency increases slightly
so, new value of frequency of \(A >\rho_{ A }\)
Now, beat frequency \(=2\, Hz\)
\(\Rightarrow\) new \(\rho_{ A }=340 \pm 2=342\, Hz ,\) or \(338 \,Hz\)
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