Pulses and waves
Vihaan is writing his EE on the way pulses behave in strings. How is it that a triangular pulse results in a sinusoidal standing wave. He is using several methods to ascertain wht happens to a sting when plucked in the middle. You can't do it in the PhET wave on a string simulation but you can send a sinusoidal pulse along the string to get a standing wave. This is quite interesting since the motion of the string is not quite what you would expect.
This might be due to the simple nature of the simulation. Algodoo is a more complex simulation and gives this result when the string is displaced in the middle.
If this is left a long time it settles into a sine wave. When the string is displaced like this all harmonics are excited but in time the higher ones are damped out leaving just the 1st harmonic. Well, that's the theory. From Fourier analysis it can be shown that a triangular pulse can be made by adding all odd harmonics. So when the string is pulled into a triangle the pulse produced when released contains all the odd harmonics. But, if this is the case where do all the even harmonics come from? Hmm.
Vihaan is also using a high speed camera to film the a string, it will be interesting to see what actually happens.