Question

When a piano tuner strikes both the A on the piano and a 440 Hz tuning fork, he hears a beat every 2 seconds. The frequency of the piano's A is

Answer 1

Answer:

The  frequency is  $f = 439.5 \ Hz$        

Explanation:

From the question we are told that

   The frequency of the  tuning fork is  $f_t = 440 \ Hz$

   The beat period is  $T = 2 \ s$

Generally the beat frequency is mathematically represented as

       $f_b = \frac{1}{T}$

       $f_b = \frac{1}{2}$

      $f_b = 0.5 \ Hz$

The  beat frequency is also represented mathematically as

     $f_b = f_t - f$

Where  $f$ is the frequency of the piano

 So

       $f = 440 - 0.5$  

       $f = 439.5 \ Hz$