In a guitar, two strings $A$ and $B$ made of same material are slightly out of tune and produce beats of…
In a guitar, two strings $A$ and $B$ made of same material are slightly out of tune and produce beats of frequency $6\text{ Hz}$. When tension in $B$ is slightly decreased, the beat frequency increases to $7\text{ Hz}$. If the frequency of $A$ is $530\text{ Hz}$, the original frequency of $B$ will be [NEET 2020]
524 Hz
536 Hz
537 Hz
523 Hz
Solution
In case of beats formation, unknown frequency,
$\nu_B = \nu_A \pm \text{beats}$
where, $\nu_A = 530\text{ Hz}$ and $\text{beats} = 6\text{ Hz}$
$\therefore \quad \nu_B = 530 \pm 6 = 536\text{ Hz}$ or $524\text{ Hz}$
When tension in $B$ is slightly decreased, then beat frequency increases to $7\text{ Hz}$. This is possible, if we take original frequency of $B$ as $524\text{ Hz}$. Hence, correct option is (a).