Question

Wavelengths of two notes in air are 83/170m and 83/172 m. Each of these notes produce 4 beats per second with the third note of fixed frequency Find the velocity of sound in air.​

Answer 1

Answer:

let wavelength L

so the frequency = c/L

Given c / (85/172) - c/L = 4

andd c/L - c/(85/170) = 4

on adding c (2/85) = 8

So c = 340 m/s

so the third note frequency is 340/L

From (1) 340 x 172 / 85 - 340/L = 4

So 340/L = 684 Hz

Frequency of third note is 684 Hz and velocity of sound is 340 m/s..

Explanation: