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...)
These are pretty great. I finished my biochem degree, coming back and watching these to make sure any gaps I might have in chemistry are filled. After seeing a lot of comments talking about their terrible university lecturers, I'm much more grateful to mine. I didn't go to any Ivy, but I certainly did learn and loved my lectures.
The quality of undergrad lectures differs remarkably little between Ivy League and ordinary schools. The main difference in m experience depends on the lecturer. Some Ivy League lecturers suck at teaching and there are marvelous no-name school professors. I have seen both. One has to get lucky. Good for you if you got lucky with your teachers. Where Ivy League can't be beat is graduate school and funding... if you depend on access to research funding and/or labs, instruments or research collaborations, then you absolutely have to try to get into the best departments there are in your field, otherwise your career will go down the drain.
Oh, I live India and I am in 11th grade. and our syllabus makers thought that it would be great idea to put Undergrad level Physics, Chem and Maths for us.
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.
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.
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
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?
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.
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.
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.
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.
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).
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.
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: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-VXeTfT8JL0Q.html
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*
@@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
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...
