Photon Energy | Physical Processes | MCAT | Khan Academy

In this video, David explains what a photon is and how to determine the energy of a photon. Created by David SantoPietro.

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[venzeti]

Very interesting material, thank you for making it absorbable and not as crazy as a photon

[praveenv]

that water analogy was really helpful..

[VickiBee]

I just read a novel (fiction) where he suggested that EMR is the source of all paranormal activity. I thought EMR was electromagnetic RESONANCE not radiation. But at the end of the book the EMR didn't work because the person who starved himself to death and made sure his body stayed in a chamber below the chapel lined the entire room with lead - which explained why the paranormal activity continued even after the EMR reverter dissipated the existing EMR.
The book was by Richard Matheson and is called 'Hell House.'

[pkdababe]

I'm not up to this part of my studies yet, but I'm so thankful to know that K.A got my back, from high school to graduation 💪

[Jess-uhfq]

So much easier to watch this then understand it from the book

[terrymiller]

Remember Hz = cycles/sec.  When you divide both sides of the equation E=hf by "cycle" you get E/cycle = joules.  What you are calling a photon is just the energy per cycle in the light wave.  It may sometimes be useful to use the particle model of light, but it does not mean that light is a particle.  A photon is not a packet of light, it is the energy per cycle in a light wave.  It is the electron that is a quantum of single charge and mass.  The photoelectric effect shows the energy/cycle of a light wave needed to free electrons.

[getreadytotube]

You are awesome. Wish I had a guy like you in high school!

[dangiscongrataway]

This is so cool and a great explanation thanks, with this information understanding waves is much easier

[VickiBee]

That's what my ex-husband did his doctoral thesis on: Photons. IDK if photons are the same as photon energy but he also knew about photon energy. He worked as a civilian contractor for the Navy at Los Alamos. He could never say what he was doing. I felt largely left out of his work.

[VickiBee]

I know someone who has a Ph.D in this stuff, and he's a medicinal chemist, microbiologist.
He did his thesis on Photon energy and I didn't understand a word of it. Even though I'm a paramedic, and he used to try to bs me into believing that what I do is as important as he does. I just didn't happen to make more than $50/hour DOing it.
In fact people want minimum wage to be higher than a paramedic's starting salary.
Paramedic's don't start at $15/hour, so if minimum wage becomes that they'll be making more than we start with.

[arthurcordeiro]

This is so interesting. As a musician, I can't help but wonder if a similar process also happens in the helm of sound. Specially when talking about methods of storing and representing sound waves through different means (digital signal x analog) it's a very common understanding that the sound waves that are audible in the real world are, by nature, continuous, as opposed to when they are stored as digital data, in which case they will exist as discrete amplitude values across the time dimension (much like a standard wave function graphic).

[VickiBee]

If you do anything as a technician, you'll find out why you need to know all this. 
I was an EKG Technician. The heart has an electromagnetic field, you wouldn't be able to record heart activity if it didn't. 
I never could get anyone to understand what the test did because they were too busy being worried it was going to shock them like a cardioverter.

[Simonjose]

If matter causes the electromagnetic spectrum, then maybe light itself isn't limited to these discrete quanta, it's merely that matter and their discrete jumps in energy levels are limited. When (an) electron(s) is/are excited to a higher energy state, it/they will always fall back down to their resting state, releasing that specific quanta of energy as a photon.

[Dyslexic-Artist-Theory-on-Time]

Could light be a wave with particle characteristics as a probabilistic future unfolds quanta by quanta, moment by moment?

[myagrimm]

Can anyone point me in the direction of a resource that explains how it was proved that photons are deposited at "discrete amounts" as was described in the video? I'm not sure where to start looking for this information, when I Google it, I don't quite get what I'm looking for

[Arntzzen]

Does this mean that a solar panel for example can either absorb all the energy of a photon or nothing? If that's the case, then does that also mean that if a solar panel is 50% efficient, it absorbs all the energy of 50% of the photons hitting it in let's say an hour and nothing from the other half?

[FrenchieDamsel]

It's under medicine because, this is a topic in the MCAT

[FroL_Onn]

I am fascinated by the look of the presentation!
Which soft- and hardware is used here?

[AvinashKumar-xfxy]

At 3:27 You said that you could either absorb no energy whatsoever or you could absorb all three but when photon travels it destroyed by coming contact with some particles etc.

[mintlata]

I understood this wow, thank you so much.