Wd-1 Resonance Tube

Aim

To determine the velocity of sound using a tuning fork to resonate a pipe.

Apparatus

  • Resonance tube
  • Tuning fork or speaker
  • Signal generator
  • C.R.O
  • Microphone and amplifier
  • Metre rule

Resonance Tube Diagram

Resonance Tube Resonance Apparatus.

Description

The speed of sound in air can be determined using the apparatus as shown. A tuning fork is struck and held above the open end of a resonance tube, the inner cylinder is raised until resonance occurs. For the frequency range 360......512 this corresponds to a 3/4 lambda mode with the open end being the antinode. The end correction may be introduced and a suitable method of elimination used if time permits. A sample run has been included for completeness.

Temperature 18°C Tube Diameter D=4.17 cm. ± .01

Which gives the speed of sound to be 342 ±4 m/s  @ 18°C.

Frequency

Length l (ave)

C=4fl/3

C=4f(l+0.29D)/3

C 512

49.0

334.5

342.8

B 480

52.2

334.5

341.8

A 456.1

55.1

335.1

342.4

A 426.6

59.1

336.2

343.0

G 406.4

62.1

336.5

343.1

C 384

65.6

335.9

342.1

F 362

69.4

335.0

340.8

Video