Very helpful, thank you!!! Much more coherent than my lecturer! (Pun intended)

It's very rare to find a video explaining exactly what I want to know, and in such a concise way. Very helpful! Thank you for making it!

EXCELLENT. There is no other way to describe this clear and concise explanation.

Successfully watched every video on this playlist! Thank you Mr.Anderson. May the mass times acceleration be with you!

@ayushsharma3988

4 жыл бұрын

I see what you did there🤣

@premsai6612

3 жыл бұрын

Nah better to say Rate of change of momentum

Nice video.

@devarya8963

6 жыл бұрын

Shivanshu Siyanwal she herself has great youtube channel for physics videos

@goodexams3064

3 жыл бұрын

@0:55 why would it fall back down again? Coz it is getting energy continuously.

@goodexams3064

3 жыл бұрын

@1:24 could you explain why?

@mrdeath4446

2 жыл бұрын

@@goodexams3064 Bro just know it that's it

Thank you so much bozeman science I hope you will continue

Nice brief introduction to LASERS.

Thank you, perfect explanation. BTW, 0:37, you confused atom with electron )

this is better than MIT, cornell open course lectures, not just better but grey color & bright clear color

In spontanious emission the energy of the emitted photon does not match to the energy level inside the atom. Theory (Wigner Weisskopf) shows that with spontanious emission the probability to get a photon with an certain frequency or polarisation is a lorentzian lineshape shifted slightly from the frequency splitting of the energy levels inside the Atom.

@dozog

5 жыл бұрын

exactly. I think he got the descriptions of spontaneous and stimulated emission somewhat mixed. You didn't mention the direction of the photon. If i remember correctly, the direction of a spontaneously emitted photon has no preference in the direction of the photon that stimulated it previously. In fact, for the spontaneous emission, it doesn't matter how the electron was excited.

Thank Mr. Anderson and youtube for letting me watch these useful videos for free.

very helpful, and beautifully explained how stimulated emission work

Sir in case of stimulated emission ,when we give energy why it comes back to the lower energy state instead of going to the next higher energy state?

@joshdheda8776

3 жыл бұрын

because the higher energy state (if it does exist at all) is highly unstable

One of the best explanation indeed !! 🙌

Excellent, most sources miss out on the avalanche effect and how that it developed within a laser.

Great video, short and to the point! Thank you.

Incredibly helpful just like all your videos, thanks a billion to the speed of light

Very helpful and really awesome way of teaching.

Bro TYSM. My Physics teacher is dog and this is literally his 45 minute lecture in 3 minutes.

my 3 days hard working through book , u describe in 4 minutes hats off

Thank you, this was a great explanation.

Short, Simple and Clear! Thanks

it was incredibly helpful !!

oh man you've finally cleared my doubt

kenny, you are correct. it is the electron that is absorbing the photons energy, however the average energy of the atom itself goes up as well as a result. both can be considered correct. it is also the electron that is giving off the photons, but again, the electron is considered part of the atom so either way you say it is right.

@Thelightsaver1

9 жыл бұрын

Robbie Eldoueik Well, I think what he says is fine if he clarifies that the atom itself doesn't jump through energy states (despite the "average energy" changing). It's an honest mistake, but misleading nonetheless.

Free energy... nice explanation.

Very nice explained

Nice Explanation.

Very informative & crisp. Thanks

Thank you so much for your great explanation, i was so stressed learning about this, and i understand everything now :D

Why atom at E2 level does not move to E3 level after being hit by a photon ?

@SogMosee

8 жыл бұрын

+amrutvani2 good question!

@yasirrahim5501

7 жыл бұрын

amrutvani2 The atoms want to be stable, going to an energy level of E3 will make it even more unstable than it already is so instead it drops to E1 and emits 2 coherent photons.

@haripanditparanjpe30

7 жыл бұрын

Alternatively I think E3 level is achieved for a transient time which of of course being unstable drops down to E2 and then to E1 , releasing 2 photons. What say ?

@FlyingJetpack1

7 жыл бұрын

The jump between level 2 and level 3 are different compared to the level 1 to 2, usually the next level requires less energy to reach that state, that means the photon that hit this electron is essentially "overshooting" the needed energy level, therefore it can only go through. But by passing by that excited electron, it stimulates it to be emitted as well.

@saranshbansal2746

7 жыл бұрын

the electron actually wont move to level E3 because the enrgy of the incident electron is E2-E1 and not E3-E2....for further excitation we need an electron of energy E3-E2 that's why the electron has no option but to relax to ground state

Is the stimulation of atom from lower energy state to upper energy state by Photon called optical pumping?

So brilliant explanation sir....... Thank you very much

Hi, Mr. Anderson, Thanks for a nice video. Could you explain "Stimulated Emission Depletion". How does depletion work? Do you have a separate video on the "depletion" part?

thank you Sir you are the best!!! #RespectFromSouthAfrica

Soooo goooood thank you sir 👍😄

Thanku so much sir.....love from India ♥️♥️♥️

Well explained. thank you so much 😄

thank you for making it simple to understand

Extremely helpful

You are Really Helping Engineering students

...Able to Get a clear cut idea about this....Thank u so much!!

Thank you ;) i finally understood what difference between spontaneous emission and stimulated emission

Short and sweet 🤘 really helpful

thank you soo much it was really very helpful .....

it was really helpful and concept clearing about stimulated emission

fast and to the point, thank you.

What is the reason for the electron in higher energy state hit by another photon to go to lower energy state instead of higher state. Why does it not go to a more higher state?

@aabidmushtaq3243

Жыл бұрын

As atoms are already in excited state that is they r not in stable state(10^8micro sec)so they Deexcite and it isn't possible for them to go to higher energy level as they are already in unstable position.

@prashantsinghsisodia6709

Ай бұрын

Not sufficient energy

excellent demonstration

Thanks sir

This video helped me understand this concept very nicely 🙂

It is not Atom that moves to energy levels but Electrons.

@SameerKhan-nd5qb

5 жыл бұрын

Electrons/atoms/ions

@dozog

5 жыл бұрын

Electrons don't move to energy levels, they move to a more outer electron band. (And that only in the outdated model of the atom) The electron moves to a higher electron band (where they have higher potential energy). as a result of that : The atom is said to be at a higher energy level. What he shows is not the model of the individual electron bands of the atom, but the energy levels of the atom. It is just a representation at another abstraction level.

@camuruckumlukas726

5 жыл бұрын

No its atoms

@i.l.zz.a.r1487

4 жыл бұрын

Electron doesn't move .its seem they teleporting .

Thank you so much Sir

Thanks for shortcut

Why does emission happen? When it "spontaneously" goes back down to the low energy state, what force made it do so, exactly? Why does it not stay stimulated?/how long does it take to decay?

Yes, yes that was really helpful

How can atom move? Isn't it that the electrons move from lower to higher energy level?

@cybrg2644

4 жыл бұрын

Yes

@musfiqsivan8750

2 жыл бұрын

same problem. How atoms can have energy levels rather than electrons. Found the same atom and energy level stuffs in my textbook but my professor said it was the electrons that moved

It's very helpful. Thank you sir!!

this was a great video !!

Incredibly helpful

Thanks, very well explained

Love this video!! So darn helpful!! Thank you!

thanks sir for this explanation

From to yilan city thank you for the explanation

Thanks for teaching ♥️ was really helpful

Nice Steve Kerr!

this is a beautiful video

That was really helpful. Thank You.

Very helpful sr

why the electron is not absorbing electromagnetic wave? Is stimulated emission is a spontaneous process? how will you explain that phase will same for stimulated emission? (if not spontaneous process)

Very helpful....give more videos like it

Thanks a lot for this.

very helpful other videos are just making it so complicated TNX

Helpful

great job it was awesome

Great video. But how do partial reflectors work? Thanks a million!

Yes! Incredibly helpful. 😊

Yes that was really helpful and I am a boy from India Assam Tinsukia

i was really looking for an explanation as to why the exited atoms releases a photon when it gets 'hit' by another photon. i don't get it. nice video though, but you didn't explain how a gas laser manages to maintain a population of exited atoms with an electromagnetic field.

@tom978i

6 жыл бұрын

If the photon allows the atom to make a transition from E1 to E2, it will not make another transition from E2 to E3 since the energy of these excited state are different, if the photon that hit the atom when it was at E2 right before falling back to E1, it will just allow stimulated emission but not making another transition to E3. However if the photon that hit the atom is exactly the energy needed to jump to E3, it will. But its not the case. hope it helps

@VinayGade

4 жыл бұрын

@@tom978i thanks for clearing my doubt

Thank you ❤️

Explained well.. helpful☺️

I have a question In a stimulated emission when we provide energy to atom why it does not take place for further excitation?

why electron comes down instead of going up

@jiyaverma9011

3 жыл бұрын

Because the incident energy is used to make a new photon instead of absorption

Suprb explanation

thankyou!! it was very much helpful

Excellent....

Why is the whole atom moving up to a higher energy level rather then just the electron?

Super helpful

LASER stands for Light Amplification by Stimulated Emission of Radiation.

It helped me a lot ...

Ur videos are awesome sir 😊

Thanks for the video and afcouse it is helpful.

yes it was, thanks

Why we get exactly the same photon ? what are the reasons for this assertion? where does it come from? 1:05

Why is the atom not further exited to the higher energy state during stimulated emission when a photon is made incident?

@sahandyman4319

3 жыл бұрын

I believe it is because the next energy level does not require the same amount of energy. In other words, the n=1 state to the n = 2 state takes a different amount of energy to the n=2 to n=3 state

Why the stimulated atom didn't absorb the energy and instead it decided to release it's energy . I can't understand why the atom decided to do that . Hope someone answer me .

Very helpful thank you

You are perfect.

That was awesome .

thank you love you