Question

A tuning fork and a vibrating sonometer wire give 6 beats per second, either with a length of the wire of 1.0 m or 1.06 m. The frequency of the fork is

विकल्प

• 200 Hz

• 206 Hz

• 212 Hz

• 218 Hz

Answer 1

206 Hz

Explanation:

Let the frequency of the tuning fork be N.

As the frequency of the vibrating string \[\propto\frac{1}{\text{length of string}}\]

For the sonometer wire of length 1 m, the frequency must be (N + 6), and for the sonometer wire of length 1.06 m, the frequency must be (N − 6), as in each case, the tuning fork produces 6 beats/s with the sonometer wire

∴ n₁l₁ = n₂l₂ ⇒ (N + 6) × 1 = (N − 6) × 1.06

∴ N = 206 Hz