MCQ
Two closed pipe produce 10 beats per second when emitting their fundamental nodes. If their length are in ratio of $25: 26$. Then their fundamental frequency in $\mathrm{Hz}$, are
- A$270,280$
- B$260,270$
- ✓$260,250$
- D$260,280$
✓
Answer
Correct option: C.
$260,250$
(c) $n_1-n_2=10$ Using $n_1,=\frac{v}{4 l_1}$ and $n_2=\frac{v}{4 l_2}$
$\Rightarrow \frac{n_1}{n_2}=\frac{l_2}{l_1}=\frac{26}{25}$
After solving these equation $n_1=260 \mathrm{~Hz}, n_2=250 \mathrm{~Hz}$
$\Rightarrow \frac{n_1}{n_2}=\frac{l_2}{l_1}=\frac{26}{25}$
After solving these equation $n_1=260 \mathrm{~Hz}, n_2=250 \mathrm{~Hz}$
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