Speed of sound

Rain invoked plan B: resonant tube measurements to obtain the speed of sound.

Forgotten: meter sticks. Problematic: Power, water off. Pouring from erlenmeyer flask works, but is noisy. 


I used a pipe to illustrate the modes.

I gathered all student data onto the board. 

Jazzlyn records data

The 8:00 section wrapped up with a lecture on the implications of the negative branch of the hyperbola. The math says the negative branch exists, but in reality negative frequency has no clear meaning.


Lilly Rose, Lisa Praise, and Daniel would work slowly and methodically, turning in the best results.

Groups that went faster obtained worse results. The process of overfilling and then backing back down to the resonance worked well. Took more time, but generated better results. The use of flasks and beakers solved the false resonance off of the empty graduated cylinders. 

Physical science can be fun?

Joyleen, Mesenda, and Leila Marie, testing their resonance depth


Measuring the resonance depth.

These distances are multiplied by four to obtain the wavelength. 

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