Ive just discovered your videos today, and although some of them are a bit simplistic, your demonstrations really are amazing. You've done an excellent job at targeting both younger viewers and college students alike.
Now, I hate to quibble, but wouldn't two photon absorption contradict your statement near the end of the video?
@grazingkow Not sure which statement you mean, but you are correct in that I have totally ignored two photon absorption in my explanations for this video. On the other hand, two photon absorption occurances are fairly rare...
@grazingkow I have a dozen or so videos filmed that need to be edited, but a sabbatical out of the country and a new son have kept me from posting anything new in nearly a year.
Sorry, don't really understand some parts. What do you mean by using KE of photon to make light? Aren't the photon itself is a light already? And, what is the "something" you are refering too? Thanks by the way for your effort in answering my questions. =D
I meant kinetic energy of the _electron_, sorry. You can harvest that kinetic energy of the electron if it collides with something (another atom/particle) and then might get light out.
You mean if an electron flies really really fast and knocks onto a proton, it gives out light? Doesn't make quite sense, no offense though. If it is true, then won't every object around us be producing light then?
Yes, it could produce light (and beta radiation - which is really fast moving electrons - hitting other atoms can produce light. This is rare, mostly the electrons will fly into and hit electrons in other materials, those electrons will jump up energy levels, then fall back down giving off light. As an aside, most things around us are producing light via black-body radiation. (ie. use infrared goggles to see how much infrared light things are giving off due to their temperature...)
Right, unless you then use the kinetic energy of the photons to make light with some other method... (ie. lightbulb, etc...) When the electron collides with something else, it might make light again.
Are you sure the electrons move to a higher orbital and drop back to produce photon? I thought it was the electron attaining enough energy to attain escape velocity to fly away from the nucleus of atoms?
Light is made of photons, not electrons, so an electron flying off wouldn't be light. It comes from electrons dropping down from higher to lower energy levels.
I think you may be remembering the photoelectric effect, which is when light comes in from outside, hits the electrons and knocks them off (giving them escape velocity) and thus causing electricity to flow out of the material...
This demo is _similar_ to the photoelectric effect but doesn't actually use the photoelectric effect.
are proton, neutron and electron are also a packet of energy? and also i cant get the part where if the light is wave, a red light is enough to glow the plastic by just increasing its intensity.
Well, protons/neutrons/electrons are thought of as particles that have mass. We now know that particles display wave-like properties (deBroglie wavelengths) and mass can be converted into energy (E=mc^2) but it is easier to not think of those sorts of particles as energy packets.
Think of a red light as waves on a beach and the plastic as a buried surfboard standing on end. A "big" enough wave could knock it over. (Thus, bright enough red light would light up the plastic.)
Meanwhile if light were a particle, it would be like throwing balls at the board to knock it over. If you threw them at the board one at a time, small balls (red) wouldn't knock it over ever, but large boulders (high energy blue light) would be able to knock the board over.
By my count I only have to watch this thing 620 more times and it will have been watched 4000 times! (I'm assuming you meant no one but me watches it... ;)
im not actually sure how to emplain white light in photon form but in wave form white light is and increased AMPLITUDE of electromagnetic radiation rather than an increased frequency light how blue is higher frequency to red, it is caused by different waves of light merging.
Actually, there is no "white" colored light. Just look at a rainbow - there isn't a white stripe. However, we perceive white light when we see a mixture of red, blue, and white light... white is the color we see when our eyes are sensing all three of those colors.
Sometimes people get misled when they later talk about blackbody radiation and how something very hot can give off "white" light - which just means the object is giving off all colors...
One photon of purple has more energy than one photon of blue light.
White light doesn't exist as a photon, it is a mixture of several colors of light (so you'd need a mix of 3 photons, at a minimum, to talk about "white light" although that would be a bit strange to talk about...)
1) Electromagnetic waves are not the same thing as light. light is electromagnetic energy in a specific wavelength (frequency). Xray, microwave are NOT light. becouse light is electromagnetic energy that is visible.
2) the difference between the reds, and blues is not the amount of energy the emit, but the wavelength (frequency) of the wave.
3)light acts as wave or matter, depending on your perspective and how you measure it.
I agree that people often assume the term light applies to electromagnetic waves that can be seen with the human eye.
However, electromagnetic waves in general are often called "light". Light you can see is then identified by calling it "visible light". This is demonstrated by the common constant "the speed of light". Microwaves, x-rays, etc... all travel at the same speed. It is not commonly called the speed of electromagnetic waves.
(2) Different colors/wavelengths of light come in different frequencies. However, different frequencies (and thus wavelengths) also have photons of different energies.
Blue photons are higher frequency than green photons, and thus blue light is often considered "higher energy"
(3) Light acts as a wave and a particle. A photon is how we describe one particle of light. It has a specific energy (like a particle does) but travels and interacts with other photons much like a wave.
If "light" applied only to energy that is visible, it would be redundant to say "visible light". It would also be meaningless to say "infrared light" or "ultraviolet light."
No, I doubt the paper is any issue as long as you don't eat it! (it is actually kind of a thin plastic and has a sticky back you could post up on a wall or something).
Just don't shine a laser pen into your eye if you're using a laser pointer to play with it...
I got a blue LED from a teacher science supply catalog.... The "purple" LED is actually a UV LED I believe...
sciencetheater 2 months ago
is the blue ligth LED? and where do i find a blue or white ligth? :)
kraenge2212 3 months ago in playlist Flere videoer fra sciencetheater
do you need a particular kind of photosensitive paper for this demo to work? If so please specify
519asdf 10 months ago
@519asdf Not really, but it IS special paper... really it is vinyl... you can order it through educational catalogs, etc...
sciencetheater 9 months ago
Comment removed
519asdf 10 months ago
Dr. Carlson,
Ive just discovered your videos today, and although some of them are a bit simplistic, your demonstrations really are amazing. You've done an excellent job at targeting both younger viewers and college students alike.
Now, I hate to quibble, but wouldn't two photon absorption contradict your statement near the end of the video?
grazingkow 1 year ago
@grazingkow Not sure which statement you mean, but you are correct in that I have totally ignored two photon absorption in my explanations for this video. On the other hand, two photon absorption occurances are fairly rare...
sciencetheater 1 year ago
@sciencetheater My advisor did his dissertation on two photon lithography, and when he explained how all that worked to me, my mind was blown.
Are you still creating these videos, or it this just a cache of your previous work?
grazingkow 1 year ago
@grazingkow I have a dozen or so videos filmed that need to be edited, but a sabbatical out of the country and a new son have kept me from posting anything new in nearly a year.
Hopefully more videos will be posted soon...
sciencetheater 1 year ago
Sorry, don't really understand some parts. What do you mean by using KE of photon to make light? Aren't the photon itself is a light already? And, what is the "something" you are refering too? Thanks by the way for your effort in answering my questions. =D
royalsnowman 2 years ago
I meant kinetic energy of the _electron_, sorry. You can harvest that kinetic energy of the electron if it collides with something (another atom/particle) and then might get light out.
sciencetheater 2 years ago
You mean if an electron flies really really fast and knocks onto a proton, it gives out light? Doesn't make quite sense, no offense though. If it is true, then won't every object around us be producing light then?
royalsnowman 2 years ago
Yes, it could produce light (and beta radiation - which is really fast moving electrons - hitting other atoms can produce light. This is rare, mostly the electrons will fly into and hit electrons in other materials, those electrons will jump up energy levels, then fall back down giving off light. As an aside, most things around us are producing light via black-body radiation. (ie. use infrared goggles to see how much infrared light things are giving off due to their temperature...)
sciencetheater 2 years ago
Wow. Thanks for answering my questions then. I shall read up deeper on these things man. Haha. Thanks once again =D
royalsnowman 2 years ago
So you mean that when the electrons attain an escape velocity, it will produce electricity but no photons are produced?
royalsnowman 2 years ago
Right, unless you then use the kinetic energy of the photons to make light with some other method... (ie. lightbulb, etc...) When the electron collides with something else, it might make light again.
sciencetheater 2 years ago
Are you sure the electrons move to a higher orbital and drop back to produce photon? I thought it was the electron attaining enough energy to attain escape velocity to fly away from the nucleus of atoms?
royalsnowman 2 years ago
Light is made of photons, not electrons, so an electron flying off wouldn't be light. It comes from electrons dropping down from higher to lower energy levels.
I think you may be remembering the photoelectric effect, which is when light comes in from outside, hits the electrons and knocks them off (giving them escape velocity) and thus causing electricity to flow out of the material...
This demo is _similar_ to the photoelectric effect but doesn't actually use the photoelectric effect.
sciencetheater 2 years ago
are proton, neutron and electron are also a packet of energy? and also i cant get the part where if the light is wave, a red light is enough to glow the plastic by just increasing its intensity.
roniepao 2 years ago
Well, protons/neutrons/electrons are thought of as particles that have mass. We now know that particles display wave-like properties (deBroglie wavelengths) and mass can be converted into energy (E=mc^2) but it is easier to not think of those sorts of particles as energy packets.
sciencetheater 2 years ago
Think of a red light as waves on a beach and the plastic as a buried surfboard standing on end. A "big" enough wave could knock it over. (Thus, bright enough red light would light up the plastic.)
Meanwhile if light were a particle, it would be like throwing balls at the board to knock it over. If you threw them at the board one at a time, small balls (red) wouldn't knock it over ever, but large boulders (high energy blue light) would be able to knock the board over.
sciencetheater 2 years ago
Where's part 3?
Merdam9 2 years ago
well i watch you channel I use a lot of these for childrens church the kids LOVE them keep it up!!
criddle24 2 years ago
Sweet. A bit of science in Children's Church. That's great.
sciencetheater 2 years ago
This comment has received too many negative votes show
Your channel sucks, no one watches it.
Just give up.
kludge11 2 years ago
Thanks for coming by and commenting!
By my count I only have to watch this thing 620 more times and it will have been watched 4000 times! (I'm assuming you meant no one but me watches it... ;)
Oh, and my mom.
sciencetheater 2 years ago
where do u get the blue light? and paper
PATHABE 3 years ago
The blue light is just a blue LED, and the paper is phosphorescent paper/plastic. You might be able to find some by searching around...
sciencetheater 2 years ago
im not actually sure how to emplain white light in photon form but in wave form white light is and increased AMPLITUDE of electromagnetic radiation rather than an increased frequency light how blue is higher frequency to red, it is caused by different waves of light merging.
mankey64 3 years ago
Actually, there is no "white" colored light. Just look at a rainbow - there isn't a white stripe. However, we perceive white light when we see a mixture of red, blue, and white light... white is the color we see when our eyes are sensing all three of those colors.
Sometimes people get misled when they later talk about blackbody radiation and how something very hot can give off "white" light - which just means the object is giving off all colors...
sciencetheater 3 years ago
mixture of red, blue, and YELLOW light...not white..
Fayer619 3 years ago
Whoops, my mistake. Thanks.
We sense:
Red, Blue, & Green light
When all three colors are combined, they make white.
sciencetheater 3 years ago
your videos are simply amazing..thnx for a science boost..
:P
Fayer619 3 years ago
wow...simple science but nicely put....would it be possible for you to put some fairly complicated bits of interesting science up??
im bored and need something to learn lol...im so sad haha
LordTeaOfBiscuits 3 years ago
Gamma rays would activate it?
bornintheusa92 3 years ago
I'm not sure. I suspect the ones that hit the paper would activate it. Most gamma rays would just go right through, though...
sciencetheater 3 years ago
AWESOME! I am just watching for fun because I actually really like science~~
PengunaFilms 3 years ago 2
Well, is white light ''stronger'' than blue or pruple light?
Matthewwong1994 3 years ago
One photon of purple has more energy than one photon of blue light.
White light doesn't exist as a photon, it is a mixture of several colors of light (so you'd need a mix of 3 photons, at a minimum, to talk about "white light" although that would be a bit strange to talk about...)
sciencetheater 3 years ago
photons are cool
shuu7777 3 years ago
do you have a PH.d? And, awesome show! i love it, keep doing more.
anpecota 3 years ago
Yes, I have a PhD and BS(w/honors) in Chemistry from Caltech.
Thanks for the compliment.
sciencetheater 3 years ago
were can i get some phosphorescent paper?
rocketcane 4 years ago
Ehem.
This doesnt seem right to me.
1) Electromagnetic waves are not the same thing as light. light is electromagnetic energy in a specific wavelength (frequency). Xray, microwave are NOT light. becouse light is electromagnetic energy that is visible.
2) the difference between the reds, and blues is not the amount of energy the emit, but the wavelength (frequency) of the wave.
3)light acts as wave or matter, depending on your perspective and how you measure it.
care to comment?
muzared 4 years ago
I agree that people often assume the term light applies to electromagnetic waves that can be seen with the human eye.
However, electromagnetic waves in general are often called "light". Light you can see is then identified by calling it "visible light". This is demonstrated by the common constant "the speed of light". Microwaves, x-rays, etc... all travel at the same speed. It is not commonly called the speed of electromagnetic waves.
sciencetheater 4 years ago
(2) Different colors/wavelengths of light come in different frequencies. However, different frequencies (and thus wavelengths) also have photons of different energies.
Blue photons are higher frequency than green photons, and thus blue light is often considered "higher energy"
(3) Light acts as a wave and a particle. A photon is how we describe one particle of light. It has a specific energy (like a particle does) but travels and interacts with other photons much like a wave.
sciencetheater 4 years ago
If "light" applied only to energy that is visible, it would be redundant to say "visible light". It would also be meaningless to say "infrared light" or "ultraviolet light."
beckster02 3 years ago
nice
DARKnDODGY 4 years ago
No, I doubt the paper is any issue as long as you don't eat it! (it is actually kind of a thin plastic and has a sticky back you could post up on a wall or something).
Just don't shine a laser pen into your eye if you're using a laser pointer to play with it...
sciencetheater 4 years ago
That's really cool! I have three kids who will love this. I found it for 20 dollars online at teachersource.
I know my kids will have lots of fun with this. Is phosphorescent paper toxic or harmful in any way?
djemil5 4 years ago