OPhysics: Interactive Physics Simulations

Interestingly the page for polarization of light has a very significant mistake in it. Since the demo allows the use of more than two polarizing filters, what is missing is the quantum effect that occurs when you have 3. When the outer two are the same polarization, and the middle one is opposing, the light will show through at approximately 50% even though it seems to be "stopped" at the second lens.

It's not the same as the double-slit example, but is related to it.

Either way, this site is really good. Unfortunately the first thing I tried to replicate didn't work because they haven't taken quantum effects into account.

Here is a video about the effect with 3 polarized lenses - it sounds crazy enough I want to add a bit of proof to avoid downvotes: https://www.youtube.com/watch?v=zcqZHYo7ONs

And here is Action Labs demonstrating something related, where light seemingly shines through a solid ball for a slightly different, but not unrelated reason: https://www.youtube.com/watch?v=TM9alPcOMcU

Not the author, just thought this was a cool collection of simulations to display physics concepts.

Recently used this one [1] to explain far/nearsightedness

[1] https://ophysics.com/l16.html