MCQ
Standing waves are produced in $10 \,m$ long stretched string fixed at both ends. If the string vibrates in $5$ segments and wave velocity is $20 \,m / s$, the frequency is ....... $Hz$
- ✓$5$
- B$10$
- C$2$
- D$4$
✓
Answer
Correct option: A.
$5$
a
(a)
(a)
The question refers to the $5^{\text {th }}$ harmonic of a vibrating wave.
Frequency of $5^{\text {th }}$ harmonic is $=\frac{n v}{21}=\frac{5 \times 20}{2 \times 10}=5 \,Hz$
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