MCQ
A string fixed at both ends vibrates in three loops. The wave length is $10\, cm$ . The length of string is .... $cm$
- A$5$
- ✓$15$
- C$30$
- DNone
✓
Answer
Correct option: B.
$15$
b
In general, the length of string is $L = \frac{{(n - 1)\lambda }}{2}$ $n \to $ Number of loops $= $ Number of harmonics in question $n = 4 \,;\, \lambda = 10\, cm$
In general, the length of string is $L = \frac{{(n - 1)\lambda }}{2}$ $n \to $ Number of loops $= $ Number of harmonics in question $n = 4 \,;\, \lambda = 10\, cm$
$L = (4 - 1) \times \frac{{10}}{2} = 15\,cm$
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