The frequencies of three tuning forks A, B and C are related as…
The frequencies of three tuning forks A, B and C are related as $\mathrm{n}_{\mathrm{A}}>\mathrm{n}_{\mathrm{B}}>\mathrm{n}_{\mathrm{C}}$. Which the forks $\mathrm{A}$ and $\mathrm{B}$ are sounded together, the number of beats produced per second is ' $\mathrm{n}_1$ '. When forks $\mathrm{A}$ and $\mathrm{C}$ are sounded together the number of beats produced per second is ' $\mathrm{n}_2$ '. How may beats are produced per second when forks B and $\mathrm{C}$ are sounded together?
$\mathrm{n}_1-\mathrm{n}_2$
$\frac{\mathrm{n}_1+\mathrm{n}_2}{2}$
$\mathrm{n}_2-\mathrm{n}_1$
$\mathrm{n}_1+\mathrm{n}_2$
Solution
$\mathrm{n}_{\mathrm{A}}-\mathrm{n}_{\mathrm{B}}=\mathrm{n}_1$
$\mathrm{n}_{\mathrm{A}}-\mathrm{n}_{\mathrm{C}}=\mathrm{n}_2$
Subtracting Eq. (i) from eq. (ii)
$\mathrm{n}_{\mathrm{B}}-\mathrm{n}_{\mathrm{C}}=\mathrm{n}_2-\mathrm{n}_1$
*