Question

Two tuning forks having frequencies 160 Hz and 170 Hz are sounded together to produce sound waves. The velocity of sound in air is 326.4 ms⁻¹. Calculate the difference between wave lengths of these waves.

Answer 1

Given: n₁ = 160 Hz

n₂ = 170 Hz

v = 326.4 m/s

To find: Difference in wavelength (λ₁ − λ₂) = ?

Formula: v = n₁λ₁ = n₂λ₂

Here, n₁ < n₂

∴ λ₁ > λ₂

∴ `λ_1 − λ_2 = v(1/n_1 - 1/n_2)`

= `326.4(1/160 - 1/170)`

= `326.4((170 - 160)/(160 xx 170))`

= `326.4((170 - 160)/27200)`

= `326.4(10/27200)`

= 3264 × 0.00036

= 0.1175 m ≈ 0.12 m