A tuning fork is in unison with a sonometer wire 80 cm long. If 2 beats are heard on shortening the wire by one centimeter find the frequency of the fork?

Explanation

To solve the problem, we need to find the frequency of the tuning fork when it is in unison with a sonometer wire of length 80 cm, and we hear 2 beats when the wire is shortened by 1 cm.

### Step-by-Step Solution:

1. **Understanding the Relationship**:
The frequency of a vibrating string (or sonometer wire) is inversely proportional to its length. This can be expressed mathematically as:
\[
f \propto \frac{1}{L}
...