I'm not from the us but you can't imagine how helpful was that for me, to see the greatest educational institution offers the help hand to all students from all countries and for free. thank you MIT on behalf of all the students
@@jaykay2218 It all depends on the teacher. Physics is the same everywhere, but when I wrote that comment, I was comparing the professor to my high-school physics teacher. My teacher only knew what it takes to solve a problem and that's what he only cared about. But this professor was much much more knowledgeable and that was visible in her teaching. I know that not all teachers in the US are like that, but at least you can find them somewhere. But here, they're very very rare
I am South African. I fully agree with you!!!! My country has been ranked last in the world in 2020 in science education.. Do the math.. (Most in my country cant...)
Thank you for revealing the truth. E = hf shenanigan is not the "internal" energy of electron. From KE = hf - hf0 we see that speed of the ejected electron depends on the frequency of light.
Because the energy of a classical wave is proportional to the square of the amplitude. It is also not quite proper to say that in quantum mechanics the energy of a wave is proportional to the frequency. The energy of the quanta that form a classical wave is proportional to the frequency of that classical wave. It is not proper to say that quanta have a frequency, though. One has to have a narrow distribution of quanta with nearly equal energies to form something like a classical wave packet with an identifiable frequency.
Maybe I'm just stubborn but I dont understand why we need to think of light as a packet after introducing E=hv. I visualize wave peaks propelling the electron instead of packets. If the frequency is too low the wave peak can't quite hit the electron in the electron shell. I should do more research about that v0. Is v0 where is becomes 100% efficient? Visualizing a beach ball tied to a buoy "x" amount of feet away in the ocean. The wave peak needs to be just right at which it breaks the rope and the beach ball/electron goes flying.
I have a doubt madam. In wave propagation water or sound , how individual particle vibrations are transmitted from particle to particle in the direction of wave propagation? There are gaps between particles in solids, liquids and gases. Is this not against principle of locality?
I remember being taught that intensity of light is related to the energy of photons through their frequency, or something like that. And I can find info saying similar things online. But here it sounds like intensity is measuring the amount of photons only? I'm sure the professor is right, but I think I'm misunderstanding something, or different people are conveying this information in different ways that is confusing me.
Intensity is the power per unit area. This is a completely classical quantity and it's valid for any spectrum. The energy of a photon, which is the quantum of energy of the electromagnetic field is proportional to the frequency of monochromatic light. The latter relationship links a quantum mechanical quantity (photon energy) to a classical quantity (frequency).
It seems the most obvious & logical explanation for a #particle acting like an #AxialWave when moving thru space is that it's orbiting something (a dark matter particle perhaps) or visa versa. It's not unlike Earth being pulled into a wobble by the moon, or a distant star's wobble evidencing planet orbits making our trajectory as we fly thru space have an axial wave (packet) as well. And since we think we know undetectable dark matter exists but don't yet know where it's distributed, this seems the most logical possibility. What do you think? This could explain the double slit experiment results, including with a detector with some interaction between the dark matter and the detector.
I am unclear why photons loss all the energy to the ejected electrons ( when Ei > workfunction) - can photons lost part of the energy to the electrons? thanks in advance for answering.
Yes, an electron can absorb part of a photon's energy. That's called inelastic scattering. It's not really proper to talk about "the outgoing photon" as the same as "the incoming photon", though. And, no, in case of the photoelectric effect not all of the photon's energy is imparted on the electron. Much of it goes to the metal's lattice.
@@schmetterling4477 thanks. This bring me to another question of this lecture> is it assuming all photons energy is fully transferred to the ejected electrons K.E. = Ei- workfunction ? am I misunderstood ?
@@ED99LAM That's correct. If the electron gets all of the photon energy, then the remaining kinetic energy is still reduced by the work function (which is basically just the electrostatic potential energy of the electrons inside the metal). At least that's the simplified theory. In practice there is also a thermodynamic component, which is why thermal emission is possible even without external sources of energy like in case of the photoelectric effect and then we can also lower the work function with an additional electrostatic field, which leads to field emission. And finally the work function can be greatly modified by surface contaminants, leading to both a suppression of emission and active emission centers. And now things get really complicated (and interesting for physicists who like to work on surface physics).
Using the popcorn button on the microwave is some of the worst advice, I thought she was smart /s Seriously though, don't use the popcorn button, it even says on most bags that the popcorn button will burn your popcorn, which is the opposite of what she says in the video.
Light does not have a speed, it has a rate of induction. Light does not exist, it's perturbations of the Aether field. Until it hits a 3D vortex, so called particle, creates a hysteresis of Illumination. Visible light is at phi:1 on the EM spectrum. Magnetism is phi:1. Photons and electrons are not particles, they are Vortices. e- >~< p+ = Aether's Hyperboloid, ~ = Inertial Plane = Infinite Capacitance. The smaller the Spacial footprint, the higher the capacitance. Aether's Hyperboloid Apex. Aether decays into e-, ~, p+. p+ enters Counterspace, 1836 p+ in Counterspace = 1 Proton as seen from Space. 1836 e- in Space. Blackhole/Counterspacial Sink is Aether's Hyperboloid into Counterspace. Stars are Aether's Hyperboloid into Space. Space was created for Aether to exist in. Aether was created for Space to exist in. Empty Space does not exist.
Misconceptions about photons. What if I told you photons don't actually move. They allow photonic energy to travel in the same way air allows sound to travel. Duality of light is a misconception, particle and a wave. Speed of Light is another misconception or worded incorrectly. It's actually the Speed of Energy. Take picture of a pendulum and see what it does (transfer of kinetic energy from one end of the pendulum to the other) and you'll have a better understanding of why/how light/energy travels so fast. The word you need to get familiar with is propagation. Photon is the particle and the energy is the wave. Photon doesn't actually travel the whole distance, that is the whole misconception.
No photons can absolutely travel the "whole" distance. In fact you can get an interference pattern on a screen (an experiment reproduced multiple times) by firing individual photons
It gives an instructor realtime feedback on how their lesson is going. She is able to see where there is confusion on a particular subject and cover it more. Here's an educator video on it: ruclips.net/video/VXeTfT8JL0Q/видео.html
The human body is also considered continuous overlaps And sectors that really relate to the factor being round We are round until Applicated shape. The desire will be met by the maker.
@@nahidparvez9010 row 2 on the right side of the asian boy. but I reckon that this may be too simple for her so she got bored as it's actually taught in high school
Really many concepts were not well explained. For example waves were badly explained as she did not explain what really a wave is? as a traveling pulse not a motion of matter. Also she always taking waves as periodic while it could be just pulses (like Tsunami) generated by an earthquake (the source) in oceans that then propagate in the medium (water). A wave is created by a source of pulses that propagate because there is a medium. The sound is a longitudinal wave where the source is your tongue moving the air and these perturbations propagate in air (the medium): sound waves cannot propagate in vacuum it need a medium. All waves need a medium to propagate except electromagnetic waves they can propagate in vacuum: Light reach earth even if almost all the distance between sun and earth is empty space except the earth atmosphere. She seems young and she should read more about physics. Also saying the wavelength is the distance between two maximums in a periodic wave which is rather a consequence of the true definition of the wavelength: "The wavelength is the distance traveled by the wave during a period of time" so is: lambda = v*T (v: wave speed and T the period). So because the time between two maximums is T and the x axis is the direction of the wave propagation, it matches the definition of the wavelength. Teaching at MIT does nit mean you really understand physics.
*BRUH* people don't have the time to read your little essay . if she has got anything wrong in the subject go to another channel . if don't understand . *MIT DOES'NT HAVE TIME TO READ YOUR ESSAY ABOUT WHAT'S RIGHT OR WHAT'S WRONG*
Either my eyes are super bad or 1 is deff the.... *me squinting super damn hard, with my bad glasses of which I cannot afford new ones, noticing there is actually a variable height throughout the chart and you could infact fit pretty much two of a into b* ... nvm.
wow...you just gotta know this...this is in line with scripture...Bible makes claims and statements about Bible and bibles....pure Bible vs.perverted Bibles...light and darkness....spirit and truth....father and son...and all kinds of proclamations of truth...
Omg. These are good. You don’t just throw equations, but explain where they come from and why they make sense in a simple manner.
Lies again? Hello Whatsapp
@@NazriB hello hello lies again!!!
I'm not from the us but you can't imagine how helpful was that for me, to see the greatest educational institution offers the help hand to all students from all countries and for free. thank you MIT on behalf of all the students
The creativity in play here is stunning!
15:50 Roy G Biv; 27:48 duality ; PE effect; 30:20 Graph freq vs KE; 31:18 Int vs KE; 33:20 h Planck constant
The more I see these videos, the more I realize that what I receive at school isn't really an education...
Considering your name, you are probably an Arab, and so am I. Here in Algeria we have the worst educational system you can think of.
Shinobi San here in America we have an “educational system” but it’s no good.
@@jaykay2218 Compared to ours. Yours is good.
@@jaykay2218 It all depends on the teacher. Physics is the same everywhere, but when I wrote that comment, I was comparing the professor to my high-school physics teacher. My teacher only knew what it takes to solve a problem and that's what he only cared about. But this professor was much much more knowledgeable and that was visible in her teaching. I know that not all teachers in the US are like that, but at least you can find them somewhere. But here, they're very very rare
I am South African. I fully agree with you!!!! My country has been ranked last in the world in 2020 in science education.. Do the math.. (Most in my country cant...)
This is an excellent lecture. Thanks, Prof. Drennan. You made me understand the wave-particle duality of light so easily.
That's cool, except that there is no such duality. :-)
This makes a lot of sense to me.
I got a clear picture when she explained the graph of KE vs Frequency
This lectures are really good!! Thank you!!!
Thanks a ton Prof. Drennan & MIT, these lectures are really helpful for my high school chemistry back here in India, and yes I promise 23:04
ikr kaysons lessons got nothing over this
Thank You Dr. Drenna. Your lectures help me understand General Chemistry better.
noob
that was so dope!!!!!! YOUR THE BEST PROF DOC DRENNAN!!
While watching the video I have a same feeling that of sitting in MIT.
Wow, these are phenomenal. I wish I had these videos when I was in highschool
Best professor of all times☢
I love these lectures, and I love professor Drennan!!!
I literally came to the US after following her classes!
Thank you for revealing the truth. E = hf shenanigan is not the "internal" energy of electron. From KE = hf - hf0 we see that speed of the ejected electron depends on the frequency of light.
Mais uma aula fantástica.
Excellent lecture!
The ejected electrons from the metal surface are also called [ Photoelectrons ]
I have more question about quantized nature of light, that I have two days ago. Maybe I will be able to solve some of them, maybe not?
This lecture is a great supplement to my courses at community college.
many thanks ,,,the topic is now easy🙏🙏
Even in 1.5 speed, it’s fairly easy to follow this teacher
2:38
3:18
3:25
3:34
3:51
3:58
4:11
4:23
4:35
It is not clear to me as to how classical mechanics says that energy of a wave has no relationship with it's frequency. 30:24 Can someone help?
Because the energy of a classical wave is proportional to the square of the amplitude. It is also not quite proper to say that in quantum mechanics the energy of a wave is proportional to the frequency. The energy of the quanta that form a classical wave is proportional to the frequency of that classical wave. It is not proper to say that quanta have a frequency, though. One has to have a narrow distribution of quanta with nearly equal energies to form something like a classical wave packet with an identifiable frequency.
Cooler than a Rockstar🙌🏿
No kidding, at Towson university, we didn’t start doing mole calculations until the last month of the course.😂
Maybe the neutrons exert a force though the protons but like a spring which we havent detected which keeps the electrons in orbit.
Maybe I'm just stubborn but I dont understand why we need to think of light as a packet after introducing E=hv. I visualize wave peaks propelling the electron instead of packets. If the frequency is too low the wave peak can't quite hit the electron in the electron shell. I should do more research about that v0. Is v0 where is becomes 100% efficient? Visualizing a beach ball tied to a buoy "x" amount of feet away in the ocean. The wave peak needs to be just right at which it breaks the rope and the beach ball/electron goes flying.
muy muy MUY BUENA PROFESORA, SIMPATICA Y BELLA, BUENAS CLASES SUPERRRRR ELLA.
Why did you tell me about ROY G BIV. What have you done.
I have a doubt madam. In wave propagation water or sound , how individual particle vibrations are transmitted from particle to particle in the direction of wave propagation? There are gaps between particles in solids, liquids and gases. Is this not against principle of locality?
Thank you this vedio is extremely helpful
it is so figurative teaching system you used
I remember being taught that intensity of light is related to the energy of photons through their frequency, or something like that. And I can find info saying similar things online. But here it sounds like intensity is measuring the amount of photons only? I'm sure the professor is right, but I think I'm misunderstanding something, or different people are conveying this information in different ways that is confusing me.
Intensity is the power per unit area. This is a completely classical quantity and it's valid for any spectrum. The energy of a photon, which is the quantum of energy of the electromagnetic field is proportional to the frequency of monochromatic light. The latter relationship links a quantum mechanical quantity (photon energy) to a classical quantity (frequency).
thanks a lot for video it is extremely helpful.
It seems the most obvious & logical explanation for a #particle acting like an #AxialWave when moving thru space is that it's orbiting something (a dark matter particle perhaps) or visa versa.
It's not unlike Earth being pulled into a wobble by the moon, or a distant star's wobble evidencing planet orbits making our trajectory as we fly thru space have an axial wave (packet) as well.
And since we think we know undetectable dark matter exists but don't yet know where it's distributed, this seems the most logical possibility. What do you think?
This could explain the double slit experiment results, including with a detector with some interaction between the dark matter and the detector.
sanjuansteve I would HIGHLY doubt that's the case
Which particle physics or QM theory do you believe best explains the universe?
i think if we can see spectrum of an atom then we can assume its change it orbital via force.
That was really impressive.Thank you very much!
I am unclear why photons loss all the energy to the ejected electrons ( when Ei > workfunction) - can photons lost part of the energy to the electrons? thanks in advance for answering.
Yes, an electron can absorb part of a photon's energy. That's called inelastic scattering. It's not really proper to talk about "the outgoing photon" as the same as "the incoming photon", though. And, no, in case of the photoelectric effect not all of the photon's energy is imparted on the electron. Much of it goes to the metal's lattice.
@@schmetterling4477 thanks. This bring me to another question of this lecture> is it assuming all photons energy is fully transferred to the ejected electrons K.E. = Ei- workfunction ? am I misunderstood ?
@@ED99LAM That's correct. If the electron gets all of the photon energy, then the remaining kinetic energy is still reduced by the work function (which is basically just the electrostatic potential energy of the electrons inside the metal). At least that's the simplified theory. In practice there is also a thermodynamic component, which is why thermal emission is possible even without external sources of energy like in case of the photoelectric effect and then we can also lower the work function with an additional electrostatic field, which leads to field emission. And finally the work function can be greatly modified by surface contaminants, leading to both a suppression of emission and active emission centers. And now things get really complicated (and interesting for physicists who like to work on surface physics).
@@schmetterling4477 thanks for taking the time to answer my questions. There are more to learn in Quantum physics.
Using the popcorn button on the microwave is some of the worst advice, I thought she was smart
/s
Seriously though, don't use the popcorn button, it even says on most bags that the popcorn button will burn your popcorn, which is the opposite of what she says in the video.
Thanks 🤍❤️
that was nice.thanks
What is the work function here mean? (38:00)
Planck constant(h) ×treshold frequency of the metal(v0)
I actually understand wavelength and frequency 😮
Thanks
Light does not have a speed, it has a rate of induction. Light does not exist, it's perturbations of the Aether field. Until it hits a 3D vortex, so called particle, creates a hysteresis of Illumination.
Visible light is at phi:1 on the EM spectrum. Magnetism is phi:1.
Photons and electrons are not particles, they are Vortices.
e- >~< p+ = Aether's Hyperboloid, ~ = Inertial Plane = Infinite Capacitance. The smaller the Spacial footprint, the higher the capacitance. Aether's Hyperboloid Apex.
Aether decays into e-, ~, p+. p+ enters Counterspace, 1836 p+ in Counterspace = 1 Proton as seen from Space. 1836 e- in Space.
Blackhole/Counterspacial Sink is Aether's Hyperboloid into Counterspace.
Stars are Aether's Hyperboloid into Space.
Space was created for Aether to exist in.
Aether was created for Space to exist in.
Empty Space does not exist.
O
7126D
Misconceptions about photons. What if I told you photons don't actually move. They allow photonic energy to travel in the same way air allows sound to travel. Duality of light is a misconception, particle and a wave. Speed of Light is another misconception or worded incorrectly. It's actually the Speed of Energy. Take picture of a pendulum and see what it does (transfer of kinetic energy from one end of the pendulum to the other) and you'll have a better understanding of why/how light/energy travels so fast. The word you need to get familiar with is propagation.
Photon is the particle and the energy is the wave. Photon doesn't actually travel the whole distance, that is the whole misconception.
No photons can absolutely travel the "whole" distance. In fact you can get an interference pattern on a screen (an experiment reproduced multiple times) by firing individual photons
Great
OMG I would have so answered that question....!! I want want want that Lego DX
1:08 1% got 24 moles - well, 12+ 12 = 24 so I guess that's their logic!
That’s pretty scary considering they are MIT students. I hope it was a troll or a technical failure.
well i got 2 moles . and my logic is very complex.
I'm Dutch, but this lecture is easy stuff for people how got electronics education
This glass is very simple
Henk ten Dolle
What?
completely agree with you I find this quite easy.
Hello dutch
I know for European people this stuff is very easy. This is America education is very easy and all get As
instead of ROY G BIV, we can memorize VIBGYOR!!!!!!!!!!!!!!!!!
RESPECT
It maybe that it becomes a wave do to the weight or interference of shadows or electromagnetic field or dark matter energy event!
12:02
roy g biv common its
VIBGYOR
do molecules ever do game theory?
I don't see the point of the clickers, it just seems like a time padder
It gives an instructor realtime feedback on how their lesson is going. She is able to see where there is confusion on a particular subject and cover it more. Here's an educator video on it: ruclips.net/video/VXeTfT8JL0Q/видео.html
@mit
They're an excellent idea!
The students that refuse to clap have some personal issues.
she seems soooooo nice
lol that first question is something I learnt in grade 10
Oo the classic, I LEARNED THIS AT GRADE .....
Im sure everyone did lol
I skipped ten grades. I basically learnt in the womb. No, I learnt it as a sex gamete.
😨😨😨😨😨scary
@@frank-ek4cy dude, I am not american so pipe down. We actually learn things in school in the rest of the world instead of having gun violence
The human body is also considered continuous overlaps
And sectors
that really relate
to the factor being round
We are round until
Applicated shape.
The desire will be met by the maker.
12:56 The asian girl sleeping
where was that Asian girl? In first bench, she was searching for something in her bag. Not sleeping.
@@nahidparvez9010 row 2 on the right side of the asian boy.
but I reckon that this may be too simple for her so she got bored as it's actually taught in high school
She wasn't sleeping. You can see her eyes open and she is wide awake a moment before.
Really many concepts were not well explained. For example waves were badly explained as she did not explain what really a wave is? as a traveling pulse not a motion of matter. Also she always taking waves as periodic while it could be just pulses (like Tsunami) generated by an earthquake (the source) in oceans that then propagate in the medium (water). A wave is created by a source of pulses that propagate because there is a medium. The sound is a longitudinal wave where the source is your tongue moving the air and these perturbations propagate in air (the medium): sound waves cannot propagate in vacuum it need a medium. All waves need a medium to propagate except electromagnetic waves they can propagate in vacuum: Light reach earth even if almost all the distance between sun and earth is empty space except the earth atmosphere. She seems young and she should read more about physics. Also saying the wavelength is the distance between two maximums in a periodic wave which is rather a consequence of the true definition of the wavelength: "The wavelength is the distance traveled by the wave during a period of time" so is: lambda = v*T (v: wave speed and T the period). So because the time between two maximums is T and the x axis is the direction of the wave propagation, it matches the definition of the wavelength.
Teaching at MIT does nit mean you really understand physics.
I mean this is an intro class that is also taught in high school... Judging to this extent just because of simplifications is kind of weird lol.
*BRUH* people don't have the time to read your little essay . if she has got anything wrong in the subject go to another channel . if don't understand . *MIT DOES'NT HAVE TIME TO READ YOUR ESSAY ABOUT WHAT'S RIGHT OR WHAT'S WRONG*
4 min energy quantized into bundles called photons; speed 186K miles /s
Stop typin' "our education system is poor". If u had good education system and a great teacher why would u come here?
💗
They "Must" Be Giants....really?
Either my eyes are super bad or 1 is deff the.... *me squinting super damn hard, with my bad glasses of which I cannot afford new ones, noticing there is actually a variable height throughout the chart and you could infact fit pretty much two of a into b*
... nvm.
👍🏾👍🏾👍🏾💙💙💙
Ytdgg
VIBGYOR is better then your song.😀🤣
wow...you just gotta know this...this is in line with scripture...Bible makes claims and statements about Bible and bibles....pure Bible vs.perverted Bibles...light and darkness....spirit and truth....father and son...and all kinds of proclamations of truth...
Very average instructor