Graphing Wavelength vs Inverse freq. or Period

[PSEYE]

According to our lab manual, the graph of Wavelength vs Period : the slope should be the speed of sound. Well, I have a negative slope of -32.2 which is ridiculous, but I can't find out what I'm doing wrong. We had 5 tuning forks , say for instance, 512Hz...the inverse
1/f = 1/512= 0.00195 , I am graphing this on the x-axis and Wavelength on the Y axis. This experiment was done with 2 tubes, one fitted into another, and you're supposed to pull the smaller tube out until the particular tuning for resonates. You are to take the distance of the pipe + the extended portion of the other pipe at 3 different places you hear resonance...then you are supposed to take the difference of the average and double it - that should be your wavelength...example

the tube is 90cm long
first trial @ 512 Hz - heard first resonance at 98.5cm or 8.5 depending...our lab instructor told us to use the entire distance so i did. Heard second resonance at 124cm, and 3rd resonance at 165. I took the difference between these three values and averaged it, then doubled it - i got 66.50cm or 0.665m I did this with 4 other tuning forks , got my info and graphed a negative slope that wasn't even close to being a straight line.

Can anyone give me a clue as to what I'm doing wrong?

Thanks.

oh btw, this is for lab : Resonance in Air Columns.

 

[Redbelly98]

If your textbook gives the actual speed of sound in air, you can use that to check whether the wavelength you get is close to what you expect for each frequency.

 

[baba89]

I understand your frustration with obtaining unexpected results in your experiment. It seems like you have followed the instructions in your lab manual correctly, but your graph does not show the expected slope. There could be a few potential explanations for this.

Firstly, it is possible that there were errors in your measurements or calculations. Even small errors can have a significant impact on the final result. I would suggest carefully reviewing your data and calculations to ensure they are accurate.

Secondly, it is important to consider the limitations of your experimental setup. In this case, the resonance in the air columns may not be a perfect representation of the speed of sound. There could be other factors at play, such as the material of the tubes or the temperature of the air. It is also possible that the tuning forks may not be producing a pure tone, which could affect the results.

Lastly, it is important to acknowledge that science is a process of trial and error. It is possible that your results do not match the expected outcome, but this does not mean your experiment was a failure. It could lead to further investigations and a deeper understanding of the concept.

In order to troubleshoot and identify any potential errors, I would recommend discussing your results with your lab instructor or fellow students. They may have some insights or suggestions that could help you understand your results better. Also, considering conducting the experiment again to see if you obtain similar results or if there are any variations.

Overall, it is important to approach science with an open mind and be willing to learn from both expected and unexpected results. Good luck with your experiment!