Description

The purpose of this experiment is to determine the speed of sound in a column of air inside the resonance tube experimentally and then to compare this experimental value of the speed of sound with the theoretical value. You will investigate:

• Propagation of sound waves in a tube
• Formation of longitudinal standing waves
• The relationship between the wave speed and wavelength of sound inside a resonance tube

Resonance tube lets you to investigate the propagation of sound waves in the tube for the measurement of speed of sound in air. Sound waves are longitudinal waves in air. In a longitudinal wave, the oscillations are along the line of travel (direction of the wave motion). The wave speed (v) is given by:

where, λ is the wavelength of the wave and f is the frequency. By measuring the difference in tube length ΔL between successive adjacent antinodes (resonances), the wavelength of the sound wave is determined as:

When the length of the air column (tube length) is adjusted to the proper length indicating “maximum sound pressure” points (resonance position), standing sound waves are set up within the tube.