Dr. Boye                                                                      Name:______________________

Physics 115                                                                  Partner:_____________________

Date:_______________________

# MEASURING THE SPEED OF SOUND

1.              Measure the number of strides it takes to walk 10.0 meters at a normal pace.  You should be able to do this to the nearest quarter mile.  Do this twice.  Calculate the average length of your stride.

Trial #1___________________              Trial #2___________________

Average length of stride: ___________________________________

2.              One person in the group should be designated as the clapper and one as the timer.  Clapper claps loudly once and all listen for echo.  Once everyone has a sense of the round trip time for the clap, clapper claps hand to set up rhythm so that you hear the sound of the clap, then the echo, then the next clap, next echo….  Equal time should occur between each sound.  As soon as this rhythm is established, measure the time it takes for 30 claps.  Do this twice.  Pace the distance to the reflecting wall and record it.  Calculate the speed of sound for each trial and average them.  Measure the outside temperature and calculate the speed of sound and compare it to your measure value.

Outside temperature            __________________

Time for 30 claps             __________________             __________________

Time for 1 round trip            __________________             __________________

Paces to wall                         ___________________

Round trip distance in meters _______________________

Speed of sound             ___________________               __________________

Average speed of sound ____________________________

Calculate speed of sound, using formula ___________________________

3.                    What is the percent error in your reading?  Percent error is found by dividing the absolute value of the difference between your value and the accepted value by the accepted value and multiplying this fraction times 100%.

Percent error     ______________________