Another thought, if you wanted to be able to change notes on a tube, is to make a sliding extension for the tubes. Something like a slide whistle (google it). That would allow for continuous frequency changes.
Just like linear kinematics but for rotations.
Linear: position = x, speed = v
Angular: position = \theta, speed = \omega
So for linear, you know x=x0+vt. Write out the similar equation for rotation and it will give you your angle in radians.
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Same concept as before: substitute...
I would love to, but as I understand it, LEDs either suffer significant red shifting upon cooling or else stop working completely. A Youtube search gave some interesting demos of this. I will check it out and report back.
Also, I looked up Luxeon LEDs and they are all rated with an operating...
Can anyone recommend a white light source to be used in a cryostat down to 77 K? We are using it in temperature-dependent studies of PV devices. Currently we have an incandescent bulb which has shifted its spectrum towards red over time and we're looking for a replacement. It would be nice to...