The Sun however has an incredible radiation pressure enough to totally blow Earth itself away. Sun's radiation pressure is one of the things that prevents it's mass from collapsing into a Black Hole.
I was wondering why a paper would be moved by a particle with extremely low mass, I mean sure they have pressure, but you'd need to have the full spectrum of EM to move/excite a paper that size in atmosphere. Hence solar sails are not used to lift vehicles to orbit. I mean, we could technically build something that can generate the required beams strong enough push stuff into orbit. And this will likely be the only viable space elevator. But the light sails, and the beams required will definitely take a while to achieve. Material science is not yet there. The only likely spots to build would be at sea, or on Antarctica due to the space needed for such a structure, and the cooling requirements that will result in the firing of the "laser" if we can still call it that. The Energy requirements would likely be incredibly high too. But all things considered, it would be a very efficient way to get to orbit...especially if we are on a planet where other means are simply not possible. PS: If you're a spider, you can feel photon pressure (their weird hairs are extremely sensitive). Also, a human eye can feel photon pressure...it's how we see. Eyes get that sweet photon pressure on cons and rods, and then we (brains) interpret it. So everyday, we feel photons. Technically, it's possible that we can feel the full EM spectrum, but this would required a significantly more sensitive nervous system...which would mean constant input...and thus probably madness. Heck, it's possible we already feel them, and we (brains) just ignore them as background noise.
just imagine what gonna happen when the humans will make it to a larger extent and try to push the sun ,so that we can have winter in summertime (just joking, don't be serious if you are a physics lover)
It. can be heat flow, but it since it describes energy rate it can describe many phenomena. With light it describes photon rate, but since the bouncing Gordon’s impart momentum, it also causes pressure, so force.
So if you were to have something that could absorb radiant pressure , would it lower the pressure at the surface of the body exerting the radiant pressure?
Yeah, I don't see it being used anytime soon. At least at optical frequencies, the amount of light needed may be destructive to the sail or the laser source, so it might be fundamentally futile. But you never know!
For a while I forgot that I studied it's force is too small and suddenly so much question came in my mind till now why was I not feeling all these and how much can we use this force, until he said it's too small. Lol
Light does exert pressure especially on atomic and subatomic particles and imparts its momentum to these particles it would be interesting to find out how much momentum is imparted say to an ion? in a Hall Effect thruster.
Glad you found it! It is also here on my TH-cam channel. All of the videos are at my channel, but on edX there are problems to work if you are interested. th-cam.com/play/PL9_sR6QqqcymZOwSp8hynhGeNTdEQp3Ji.html
An electron beam won't go too far in the air because it will collide with gas molecules and water droplets. If you ignore those, how much momentum the beam would impart depends on how many electrons are in it and how fast they are going. I don't have much intuition to know it if would be a macroscopic pressure since we never "play" directly with electron beams.
@@Prof-Hafner when I was at uni we did one experiment called the compton effect in which gamma photon impart momentum to electrons. I also believe beta radiation can travel roughly 6 feet in air. But, as you say.. maybe the CRT is too weak or doesn't provide enough energy. However, the electrons must have been able to travel some distance in the compton experiment, because we were measuring deflection... although it was a number of years ago now.. quite a number.. maybe I was measuring a shift in wavelength with angle and then using that relationship with conservation of energy... hmm As a side note.. I wonder if an electron would travel further through an already ionised air than otherwise for the same given energy..
@@joecater894 one keyword to use to read up on this is "annealing", because I think electron beams (presumably not in high vacuum) are used to modify materials in certain industries.
They had us in the first half, not gonna lie
Yeah 😂😂😂
I was almost ordering a laser to try that.
imagine close the video too son and going to your physics teacher to do the demostration
I know! I have a little bit of guilt over this one.
I feel so dumb, completely fell for it lol great way to demonstrate though
Haha sorry. I carry a lot of guilt over this demo, but I think people remember the lesson well. :)
The Sun however has an incredible radiation pressure enough to totally blow Earth itself away. Sun's radiation pressure is one of the things that prevents it's mass from collapsing into a Black Hole.
Never gonna end the video till the end from now on
“This Professor would be SO hot with a short haircut” -my friend watching with me.
Ha! They should watch The Tao of Steve.
Really appreciable very good explanation sir thanku so much for such a good video
He's joking
I had a physics treacher who actually showed us this video during class, completely dismissing the part in which he says is a joke.
Oh no!!
Some months ago a satellite orbit has been raised using radiation pressure. :)
Have you seen the High-efficiency triple-helix solenoid beam that can theoretically pull items into itself? Highly recommend checking it out.
laser radiation pressure propulsion systems will be our ticket to space time travel
Great presentation. Thanks.
I was wondering why a paper would be moved by a particle with extremely low mass, I mean sure they have pressure, but you'd need to have the full spectrum of EM to move/excite a paper that size in atmosphere. Hence solar sails are not used to lift vehicles to orbit.
I mean, we could technically build something that can generate the required beams strong enough push stuff into orbit. And this will likely be the only viable space elevator. But the light sails, and the beams required will definitely take a while to achieve. Material science is not yet there. The only likely spots to build would be at sea, or on Antarctica due to the space needed for such a structure, and the cooling requirements that will result in the firing of the "laser" if we can still call it that. The Energy requirements would likely be incredibly high too. But all things considered, it would be a very efficient way to get to orbit...especially if we are on a planet where other means are simply not possible.
PS: If you're a spider, you can feel photon pressure (their weird hairs are extremely sensitive). Also, a human eye can feel photon pressure...it's how we see. Eyes get that sweet photon pressure on cons and rods, and then we (brains) interpret it. So everyday, we feel photons. Technically, it's possible that we can feel the full EM spectrum, but this would required a significantly more sensitive nervous system...which would mean constant input...and thus probably madness. Heck, it's possible we already feel them, and we (brains) just ignore them as background noise.
just imagine what gonna happen when the humans will make it to a larger extent and try to push the sun ,so that we can have winter in summertime (just joking, don't be serious if you are a physics lover)
@@noone0978 don't forget tthat recoil force by he laser would be able to kick of earth from solar system if we really get that powerful laser😂😂😂
@@futurebillionaire369 yes
Amazing!
I fell for this so hard lol. Hand on my head and everything 🤣
And they still wanna reach 60% speed of light by using solar sail haha
Yeah but not having to carry the fuel is sooooooo seductive!
The wattage of the laser is a measure of heat, not force.
It. can be heat flow, but it since it describes energy rate it can describe many phenomena. With light it describes photon rate, but since the bouncing Gordon’s impart momentum, it also causes pressure, so force.
the neowise comet brought me here and i almost fell for it XD
Good ❤❤❤
Thanku sir
radiometer?
So if you were to have something that could absorb radiant pressure , would it lower the pressure at the surface of the body exerting the radiant pressure?
More over would lowering the radiation pressure of a zone of the surface of the sun cause a solar flare or mass ejection?
Not implemented in space travel till 9092.
Yeah, I don't see it being used anytime soon. At least at optical frequencies, the amount of light needed may be destructive to the sail or the laser source, so it might be fundamentally futile. But you never know!
Is it a clickbait??
"Well Yes , but actually No"
👏
Superb
I trusted you. 😢
For a while I forgot that I studied it's force is too small and suddenly so much question came in my mind till now why was I not feeling all these and how much can we use this force, until he said it's too small. Lol
Light does exert pressure especially on atomic and subatomic particles and imparts its momentum to these particles it would be interesting to find out how much momentum is imparted say to an ion? in a Hall Effect thruster.
Light has no mass therefore no momentum
Wow sir
very good experiment
where am I able to watch the full videos?
I found it!!
find at EDX!
Thank you sir!!!!!! I really love you!
Glad you found it! It is also here on my TH-cam channel. All of the videos are at my channel, but on edX there are problems to work if you are interested.
th-cam.com/play/PL9_sR6QqqcymZOwSp8hynhGeNTdEQp3Ji.html
I am wanna ready to go for making a gadget before completing the vedio.🤔🤔🤔🤔🤔
Sorry about that. :)
Wow..🤐
what if you took the electron projector from a CRT old TV... then fired that beam at it?
An electron beam won't go too far in the air because it will collide with gas molecules and water droplets. If you ignore those, how much momentum the beam would impart depends on how many electrons are in it and how fast they are going. I don't have much intuition to know it if would be a macroscopic pressure since we never "play" directly with electron beams.
@@Prof-Hafner when I was at uni we did one experiment called the compton effect in which gamma photon impart momentum to electrons. I also believe beta radiation can travel roughly 6 feet in air. But, as you say.. maybe the CRT is too weak or doesn't provide enough energy. However, the electrons must have been able to travel some distance in the compton experiment, because we were measuring deflection... although it was a number of years ago now.. quite a number.. maybe I was measuring a shift in wavelength with angle and then using that relationship with conservation of energy... hmm
As a side note.. I wonder if an electron would travel further through an already ionised air than otherwise for the same given energy..
@@joecater894 one keyword to use to read up on this is "annealing", because I think electron beams (presumably not in high vacuum) are used to modify materials in certain industries.
@@Prof-Hafner that sounds interesting. I'll look that up. thanks.
😂😂
😂
Um.... Bro...
Come on, you can do better than that. Put the paper in a glass box, do it again
You won't get an macroscopically observable force with a laser pointer.
Fake demonstration...leser lite has no enough energy to move rider in atmospheric pressure.
you don't have to mention it he already confessed in the middle of the video ...