I show you the real reason why a Crookes radiometer spins See the original video here: • Shining 100,000 Lumen ... Subscribe to my other channel here: / theactionlab
At UofA college Physics lab many many years ago I built a radiometer located inside a high vacuum chamber. I vacuum deposited aluminum on one side and carbon black on the other side of the microscope coverglass slides. Plotting rotation as a function of vacuum pressure with a 1KW light illuminating the radiometer, as the pressure dropped the radiometer spun away from the black side then as pressure continued to drop it stopped rotating as pressure continued to drop it began s[pinning away from the aluminum mirror side. Black is thermal, Mirror is photon pressure.
When you said different colours I thought of the light, which I wonder if it'll spin faster at higher frequencies or in reverse if meeting radio. Probably not the later.
I have use a magnifying glass and focused the sunlight on the white side making it spin in that direction then on the black side making it spin in that direction.
The brightness of the sun is about 127,000 lumens *per square meter*. About 98,000 lumens / m^2 after passing through the atmosphere. You can't compare that directly to the flashlight. We could estimate if we knew how wide the flashlight was, what angle the light emerges with, and how far away it was... or James could just tell us.
if its 100,000 lumens bright, and it is shined at something less than a meter away, it would be brighter than atmosphere influenced sunlight. if you press it up against the wall then it will be even more bright.
@@spiritorange8325 How do you know she wasn't just wrong? Which is obviously likely and all being that teachers are so known for telling students lies to manipulate things for some unknown reason. Derp
Photons don't have mass but they to have momentum. Maybe this photon momentum is providing a push to the vane dark sides....absorbing photon momentum. I used a blue laser like yours on the program.......Very good science (and safety) show I think.
Hi,love your videos ! Can you make a video using the vacuum and a ultrasonic sensor like hc-sr04 and simulates mars air presure and see if it can move some fine dust?basically i'm curious if solar panels on mars rover can be clean with something cheap ..because they prefer to put some lab tools insead of wipers and the rovers are not design to last more than 2 years so dust on panels are not a concern..but anyways i'm just curious !
Static electricity from the dust devils cleans off the panels. This was discovered after The Martian movie came out, so they still thought Mark Watney would have to clean them off by hand.
What air is being heated? The bulb is under a vacuum...... I used to own one and my mother knocked it off a shelf. When it hit the floor it popped just like a flourescent tube does.
Action Lab Shorts, to bad you won't read the message. I dare you to put that bulb into some tests to see how fast you can get it to spin in the other direction. 1. A bucket of ice 2. Your beverage chiller 3. Liquid nitrogen
All I’m hearing😭 “White side black side because black white radiation heat light bright side…” Time I’m nodding and gaslighting myself into thinking that I understand the explanation😂💗
That's interesting. I'd always heard the 'pressure' explanation before. Apparently if you actually get a 100% vacuum the white side does spin more quickly.
Uhm... Would it be all possible to hookup a turbine to this to charge a battery... Would it actually be able to charge a battery... The sun does push out a lotta heat? Just wondering.
How many Crookes radiometers can be powered by the same light source, and how fast would they need to spin to produce enough energy to exceed the energy needed to power the light?
@@pente12 not necessarily. The laws of thermodynamics are in balance across the entire universe, so if there is a surplus in one spot matched by a deficit (such as a Star being swallowed by a black hole) somewhere else, the laws remain unbroken.
@@pente12 More to the point, we don’t even use most of the energy we produce-by a huge amount. In the 1880’s, Oliver Heaviside decided to investigate how much energy was being produced versus how much energy landed in the wires. His result had thirteen zeroes in it. Shocked, he went and got a bigger envelope. His second answer also contained thirteen orders of magnitude. Realizing that no one would ever believe him, he declined to publish his findings officially. For context, this is like using one hurricane to drive one sailboat, and upon trying to drive a second sailboat using the same hurricane, being told “No! You must use a separate hurricane for each sailboat, or else you are breaking the laws of thermodynamics.” If I have twenty trillion dollars, and bread is two dollars per loaf, then if I want multiple loaves for my money, am I a believer in “free money” pseudoscience?
@@dr.jamesolack8504 as long as you believe that, you will never produce a surplus of energy. You must assume that the beast can be defeated before you will put in the effort to defeat it. Otherwise, you will desist at the first, most elementary obstacle.
What is the difference between the 2nd incorrect explanation and the correct explanation? 2nd mentions pressure, correct mentions particle force, which is basicly the same. In both explanations it is air being hotter on one side so having more pressure/force against the vane. The whole “block other molecules from reaching it” doesn’t seem to make any sense. It’s a low pressure gas, differences in temperature/pressure increase circulation, not that this would be needed, since its a gas.
Action Lab: I've enjoyed all your videos except this one. I don't understand the Thermal Transpiration explanation. I don't understand the figure. Can you please provide a more detailed figure and a stepwise explanation?
