Two stretched strings A and B when vibrated together produce 4 beats per second. If the tension applied to string A increased, the number of beats produced per second is increased to 7. If the frequency of string B is 480 Hz initially, the frequency of string A is
Show Hint
When tension increases, frequency increases. Use this to determine the correct frequency shift in beat frequency problems.
Beats are given by:
\[
|f_A - f_B| = 4
\]
Since \( f_B = 480 \), we have:
\[
f_A = 480 \pm 4
\]
So, \( f_A \) could be 476 Hz or 484 Hz.
When the tension in A is increased, the frequency of A increases. This means:
\[
f_A480
\]
\[
|f_A - 480| = 7
\]
\[
f_A = 487 \text{ or } 473
\]
But since f\(_A\) was initially either 476 or 484, the correct answer is 484 Hz.