trinitaet

I am really sorry to tell you this, but I am frankly a bit disappointed in you guys... Whenever there is some topic where you should do some scientific research up ahead, you almost never seem to do it. "...it's totally graphite. Uhm... which I guess is carbon..." just nailed the coffin there... It is not as if you need to build you own physics lab or whatever, but it takes about 2 minutes of googling to find the properties of graphite, INCLUDING the baseline thermal conductivity. You do this for a living, please bother yourself with doing this!

@AlexTheGreatish would be able to say for sure, but my understanding from the video is that it has different conduction ratings for horizontal & vertical conduction, rather than having different ratings for x & y. So that is to say I don't THINK it would matter, but I don't know for sure. Since graphite basically is layers of hexagonal carbon atoms, there is no difference in "x" or "y". What matters is, if you measure the (thermal) conductivity along the layers or the conductivity perpendicular to them. The coupling between the atoms inside a layer is much stronger than the one between the layers and so, there will be a difference between the "z" axis and the ones, that span your layer.

The tape does not have to touch the mirror, but the smoke of the tape being evaporated precipitates on the mirror, and can harm the sensitive, dielectric surface. I once accidentally killed an expensive Nd:YAG-Crystal as well as the mirrors used in the cavity, because I burned a detector card with the pump-LASER. Hooray for insurance! To be honest, the day after I wrote the reply I showed the video to some guys from one of our laser labs and they literally cringed

Uhm... Are you aware you significantly decreased the lifespan of your dielectric mirrors by using the "tape" method instead of a proper calibration by using several diaphragms and IR-detector-cards?

I am sad... I used my red/blue 3D glasses, whey Linus sad it was the most 3d keyboard, but it just didn't become 3D.

Ok, I might be a bit late on this one, but I had to register to point out something. At 4:23 they present a formula to derive Hc . The problem with this is, that it makes absolutely no fucking sense at all (please excuse my profound language, but these things really annoy me as a physicist). At first, there is a sum of a scalar without a unit at all and a velocity (usually in m/s) and to top it of they sum it again with the square root of a velocytiy, which is simply not allowed... like.. never. If somebody would do this in a physics or engeneering exam, he would be kicked out by all of us tutors. Furthermore, the formula given here does not even match in units (not that you even could assign it a unit AT ALL) with the one given at 4:15... Ok, sorry for the fuzz and I am quite sure, that no one will ever read this, but at least I will be able to sleep tonight.