Crookes Radiometer

[nonmathposn]

ข้อสอบมหิดล ปีนี้ มันออก เกรียนมากTT

[ToUFuMaNsan]

@nonmathposn ใช่ๆ ปีนี้ออกเรื่องนี้ข้อนึง เราเข้ามาดูเพราะสงสัย ไม่น่าเชื่อว่าจะมีคนมีโพสต์ 55 5 เธอทำข้อสอบได้เยอะมั้ย

[Prublixa]

doesnt the music suit the radiometer - eh eh lol !!

[panzarw]

its easy to explain,the colored sides receive different amounts of energy. 

[gabrielbenitosobrino]

tengo un radiometro igual que ese

[petersplim]

This is probably one of the most difficult phenomenon to explain the particle (photon) theory of light....:) Good vid. Thanks

[YDsixstring]

Sorry Pete, no photon physics here.

Put the mill in your (dark) freezer and it still works!

The answer you're looking for is called Thermal Transpiration.

The vast majority of ppl can't explain how this device works. In short, there are SOME air particles in a NEAR vacuum that move freely. When the temperature differential inside changes the air molecules get sucked over the perimeter of the vanes like the difference b/w hot and cold air on an airplane wing.

[vik95170]

waw great 6 stars

[renatadevin]

Well I have a a question,

Why isnt this bieng used for electricity? You have away to make something spin, so put a turbine on it!

[Bruwulf]

Because radiometers only work under artificial conditions... a particular level of atmospheric pressure, on a nearly-frictionless spindle, with a very lightweight set of vanes. The latter two conditions are key. The actual amount of kinetic force generated by this effect is minuscule, pretty much exactly enough to turn the vanes. It couldn't turn anything.

[renatadevin]

oh...I am sad now

[DRNEGOLICIS]

what do you mean put a turbine on it?

[edrammeh]

@renatadevin Takes energy(heat) to cause motion. Not a sufficient energy source. It would be like using 10 gallons of gasoline to power a light bulb for 5 min(exaggerating).

[yuandrew]

Phil,

I recognized the object in the background immediately; it's a cone-type electric heating element similar to the one on a Presto "HeatDish" brand space heater with a Variac wired to it to control the output.

It's the infrared heat from the coil that's making it spin in this video.

[Philiprubbo]

Dear You Tube

I understand using white light, infrared, or color lights that they cause Crooks Radiometer spindle to turn, but the device in this experiment looks like some sort of cooling apparatus and not light radiance at all. So cooling direct to the radiometer will also cause the spindle to turn?

Phil