PHYS 130 Lightwaves Part 5: Newton's Rings

Video lecture for PHYS 130 at the University of Alberta. Newton's rings was a phenomenon discovered by Sir Isaac Newton. It is an interference effect produced in a thin wedge of air between the spherical surface of a lens and a flat pane of glass. It is often used by lens makers to check that the surface of a lens is perfectly spherical.

[jiefan]

There is a much simpler way to do your derivation from 3:00 to 8:00. Instead of using the triangles you used, you only need one triangle: from the center of the circle C, to N, to Y. Length CN is r - t. Length NY is x. Length CY is r. By the pythagorean theorem, (r - t)^2 + x^2 = r^2. Expanding and cancelling gives you t^2 + x^2 = 2rt.

[soulhouse]

This is my first time watching your video profssr. I’m really impressed. Your explaination and method of problem solving are brilliant. You just earned new subs😃

[christianjourneytv]

I have never commented on a video but this impressed me. I've never found such explanation. Thanks.
I wish i could explain like this.

[haniefsofi]

You should have made videos for various Other optics concepts. That would have been helpful. Your method is nice .

[boudzzzzsssdddfffg]

Very clear explanation this one, thx very much!

[cansucorbac]

i liked how the video started and ended as a spongebob episode:) and also sir, i should say that we really can feel your enjoy when you're explaining the physics behind. (sorry for bad England btw :, D)

[jamesbutler]

Why are you are using a converging lens instead of a plano lens?

[helium]

Is this related to the paradox where thicker glass can sometimes transmit more light than thinner glass?

[PAA-nepc]

This newton, I wish he was still alive