Physics Mastery Lab

Decent Essays
Speed of Sound Lab Report
Jamie Cook
PHYS 1114: College Physics I
Oklahoma City Community College
December 10, 2013


The purpose of this experiment is to measure the speed of sound in air and to determine the effects of frequency on the speed of sound.

Apparatus (equipment used):

Signal generator: manufacturer- EMCO, model number- SS-1, range- 20Hz-2MHz, least count- 1Hz
Frequency meter: manufacturer- DEADALON CORPORATION, model number- N/A, range- 20Hz-2MHz, least count 1 kilohertz
Oscilloscope: manufacturer- BK Precision, model number- 1472C, range- 0-15MHz, least count- 1 Hz
Speaker: manufacturer- Western Electric, model number- D17312, range-
…show more content…
In this experiment, the signal generator was set so that the frequency meter showed a reading of 1,803 Hz. The microphone was moved to a distance from the speaker so that the oscilloscope displayed a straight diagonal line. This position was of the microphone was recorded as the initial position, or beginning of a wavelength. The microphone was then moved farther in the same direction until the oscilloscope displays the same horizontal line. This position was recorded as final position, or the end of the wavelength. The distance between the two positions represents one wavelength for this frequency. This was repeated for frequencies of 2,402 Hz, 3,002, Hz, 3,602 Hz, and 4,201 Hz.

Method continued:

Data analysis: After the positions were recorded for frequencies 1,803 Hz, 2,402 Hz, 3,002 Hz, 3,600 Hz, and 4,201 Hz, the wavelength was determined for each. This was done by subtracting the initial position from the final position (position final–position initial=wavelength). Using the calculated wavelength, the speed of sound in air at each frequency was determined by multiplying the wavelength by the frequency (speed of sound=wavelength x frequency). By adding the five speed values and dividing by the number of speeds, the average speed of sound was calculated. Then 344 m/s was used as the accepted
Get Access