Lab 5: Standing Waves

Lab Purpose:
     Analyze a wave that is affected by an external force, which in this case is a function generator
     combined with a frequency generator.

Part 1: Experiment
     We setup a function generator attached to a wave driver which is then attached to a length of string.
     We then vary the frequency until we get standing waves and note the frequencies obtained.

     Equations necessary:
     2L/λ = n
     v = fλ
     v = sqrt(T/μ)

 

Harmonic #	M =.2 kg	M =.05 kg
1	13 Hz	6 Hz
2	26 Hz	12 Hz
3	39 Hz	18 Hz
4	51.5 Hz	24 Hz
5	64 Hz	32 Hz
6	77.2 Hz	39.2 Hz
7	90.1 Hz	46 Hz

The average ratio is 2.08, which is close to the expected ratio which is the square root of the ratio of masses or in this case the square root of 4.  The wave velocity as determined by the graph is 62.73 m/s, which deviates significantly from the expected 40.4 m/s.
The error is a notable 55%.