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We look through windows every single day, yet the fact we can see a clear image through them is actually kind of amazing - this video explains why.
More garlic: https://www.youtube.com/watch?v=LT1UuQO2C6g
Snell's Law: https://personal.math.ubc.ca/~cass/courses/m309-01a/chu/Fundamentals/snell.htm
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Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute!
Created by Henry Reich
Produced by Joshua Chawner
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As a glasses wearer, I'm always looking through windows.
0:28 As a Linux user I can confirm that the fact that windows work at all is a miracle
Also my car's windshield is curved yet I can see the road fine.
0:16 hey I know that garlic
With Snell's Law you also get Snell's Window where light is bending from air to water so much that if you are underwater and look up you can only see a small circle of what is above.
As an optical engineer I stumbled across flatness artifacts in some of our setups. If you want to reflect light from optical filters you need certain flatness specs < the wavelength of light. When coating filters, actually both sides of a thin glass piece will be coated, so the forces correct on both sides. Even when the glass is perfectly straight, tension introduced by the window frame easily creates artifacts as well.
What a relief to see that your laptop screen also has the kind of marks mine has :D
From a historical perspective, there is a difference between Snell's law and the law of refraction, and I think the distinction is interesting enough to share here. The law of refraction, given in the video, was originally about mechanical waves (where the speed can be calculated). Snell's law was applied to light and was formulated in terms of the index of refraction, and was discovered at a time when we didn't know what the speed of light was, nor did we know the connection between the speed of light in a material and the index of refraction. Of course, now we know what links the two, and Snell's law is equivalent to the law of refraction to the point where in most places they are considered the same thing, but from a historical perspective there was a difference.
1:42 bits like this are what turn good explanations into GREAT explanations.
It's important to note that the effect from inside at night (with lights on) looking out is also less obvious because we inhabit much small spaces with reflected objects located at a much closer distance, thus the less drastic looking distortions.
i did it. this is the first minutephysics i have watched in probably 10 years where i already knew the correct (!) answer before watching it. :) i never felt so smart in my life before. thank you.
Wow. This is going to change the way I look at the world in a huge way.
The background music could be acceptable if it was way quiter.
0:27 in an interview with astrophysicist Brian Cox, Philomena Cunk claimed mirrors are a miracle. It seems like she was close
A clear image through wavy glass is one of those everyday miracles you never think to question. Windows earn a little more respect after this.
Look at that!!! Henry also got his Garlic Plushie!!
Dang. I don't look through enough people's windows, because I have never noticed this.
Was not expecting to see Birmingham (UK) in the second reflection shot!!!
The way you break down counterintuitive physics with simple line drawings always reminds me why visual models beat paragraphs of text every single time. Brilliant breakdown!