Particle Physics (17 of 41) What is a Photon?

In this video I will introduce photon as a piece of energy, having no mass traveling at the speed of light, acts like a particle, having momentum, and having energy that is quantized.

Next video in the Particle Physics series can be seen at:

[bishnutripathee]

What does the term "photon can actually bump it like a billiard ball bill bumping another billiard ball and making it move" mean?

[rutvikrana]

one thing to
How does photon / light reflect??

Like as we see in normal things Newton third law of motion is the reason of reflection of an object.... But we see microscopically the protons of both objects repels each other.. So this is actual reason of

Now if photon does not have mass and charge how it can repel .... ??

So basically my question is how reflexion occur in photon / light...

[cescargot]

Nice lecture ! Always heart breaking to see profesionnals use "sec" for Second SI unit, which is actually "s" only. Having γ used for photon instead of "photon" would have been great also. All this, does not help the public audience to get used to standardized units to ease things for everybody on a middle term basis. Meanwhile, Km, Kph, sq m & al will still be there 😒

[malikfahd]

Man, keep up with the good work. The content and structure of your lecture was amazing!

[sahilverma]

there a other think also going on on earth
this professor is 3x10^8. time better than my teacher how teach the same thing in my school 😂😂😂😂😂

[garthenar]

Your my hero. I need this for a class right now but I'm going to do this, the E&M playlist, and review with you over the Summer. I've always hated school but with you I actually get to sit down and enjoy the material. I've set up a channel under a different name and I'm hoping to have a laser done by the end of the Summer AND be able to explain why it works.

[deadsheep]

photon is what controls everything...you, me...everything! it is what lights up those images in your head and controls your body.

[zakirhussain-jsku]

I think a photon has some properties of mass. It is affected by gravity, has Kinetic Energy, can produce electron & positron both mass bearing particles. Concept of massless photon comes relativity. Is there any conclusive evidence that photon has no mass. Electron & positron produce photons, both Electron & positron have mass. I think 1 directional motion of photon is due to its mass since electric & magnetic flux only oscillates in opp. directions. Particle like action of photon is due to its mass. Wave behaviour of photon is due to Interaction b/w fluxes. I know this is not what current thinking is but I am curious about photon having no mass. I think all stable particles must have mass, electric & magnetic charge.

[DailyEventsWorldwide]

Thank you this explains so much right now. Are we experiencing a Photon event right now?

[hiunchen]

Such a great place to come when it's summer. Your videos are clear and easy to understand. Thank you.

[zakmatew]

I know I will be attacked for my statement but I will share it anyway.Light does not consist of photons and has no speed. It has a rate of propagation and it depends entirely on the medium it goes through. Light is waves or disturbances that are completely invisible until they encounter a target....

[rtsx]

ya NO mass HOWEVER it HAS momentum .... good luck with that one

[zakirhussain-jsku]

When electric charge oscillates in free space photons emerge from space, they stretch with expanding space, lose their energy to space & ultimately dissolve back into space. Could the photons be made of Space itself. If so the entire Matter & Energy could have emerged from Space.

[jopo]

Hello Michael. hoping you can point me to one of your many videos that would explain the concept of the "Photon Gas" I am seeing it being used in the sense the Photon gas actually has a temperature. This seems absurd to me. My understanding it is a useful concept when used in astrophysics.

[niblick]

Plancks' constant is not 'joules per second'. It is joule second. Two different things.

[angoor]

Interesting stuff but the math you presented exceeds my pay grade as a truck driver. Sometimes I equate my truck as a giant photon moving at 70 miles an hour delivering goods to mostly an unappreciative universe. I wished I had taken math more seriously in school. Thanks for the post.

[ver]

Excellent explanation, thank you, and you have another subscriber.

[spark]

Wonderful! Oh thank you for this. This is the best physics lecture I have ever had. My interest and love for the subject is rekindled because of my chance discovery of this video.

[dalenassar]

At the end... I LOVE the little blooper moments--you should do this in all that actually contain them--I know I come up with many in "live" lectures: They actually bring up good points that otherwise drift away into the ether (why do we use that expression still?) If it cuts too deep into the time available, then cut out some of the live calculator button presses! Then maybe one dedicated video...remember Walter Lewin's "dotted line" video?

[VolkerThebrathGuitar]

Thank you so much. I made a huge step forward in understanding.