A string of length \(l\) is fixed at both ends and is vibrating in second harmonic. The amplitude at antinode is \(2\) mm. The amplitude of a particle at a distance \(l/8\) from the fixed end is:
| 1. | \(2\sqrt2~\text{mm}\) | 2. | \(4~\text{mm}\) |
| 3. | \(\sqrt2~\text{mm}\) | 4. | \(2\sqrt3~\text{mm}\) |
A string of length \(3\) m and a linear mass density of \(0.0025\) kg/m is fixed at both ends. One of its resonance frequencies is \(252\) Hz. The next higher resonance frequency is \(336\) Hz. Then the fundamental frequency will be:
1. \(84~\text{Hz}\)
2. \(63~\text{Hz}\)
3. \(126~\text{Hz}\)
4. \(168~\text{Hz}\)
| 1. | \(L\) | 2. | \(2L\) |
| 3. | \(\dfrac{L}{2}\) | 4. | \(4L\) |
| 1. | \(3:1\) | 2. | \(1:2\) |
| 3. | \(2:1\) | 4. | \(1:3\) |
The length of the string of a musical instrument is \(90\) cm and has a fundamental frequency of \(120\) Hz. Where should it be pressed to produce a fundamental frequency of \(180\) Hz?
| 1. | \(75\) cm | 2. | \(60\) cm |
| 3. | \(45\) cm | 4. | \(80\) cm |
| 1. | \(13.2~\text{cm}\) | 2. | \(8~\text{cm}\) |
| 3. | \(12.5~\text{cm}\) | 4. | \(16~\text{cm}\) |