Fluorescent Lamps Explained with Quantum Physics - A Level Physics
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- Опубліковано 25 сер 2024
- This video introduces fluorescent lamps and explains them with quantum physics for A Level Physics.
These common light fittings are used because they are relatively cheap and highly efficient. A glass tube is filled with mercury vapour at a low pressure. When excited by electrons the mercury atoms become ionised, losing an electron. As the electron returns to its ground state, it then emits an ultraviolet photon. A phosphor coating on the inside of the tube then absorbs the UV photon, finally emitting a range of visible photons which we see as white light.
Thanks for watching,
Lewis
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*breaks the tube
"maybe some gas coming off, maybe some mercury, could be a hazard" 😅
Great video though 👍
btw never do what he did! the phosphur (I think?) on the coating of the glass is really bad if it gets in a cut, which is especially bad because of all of the glass shards due to smashing it
No Gloves + No fume hood? +mercury vapor?
=life on the edge
@@PhysicsOnline no way respect but please be safe
@@PhysicsOnline youre too funny
Watched this in my physics class today , my teacher is jealous of your uranium marble
I think I bought it on Ebay!
hi, this is a very good explanation, from an international teacher point of view! keep up the great work!! could you maybe explain the light of a phone, its touch screen, in terms of quantum physics?
Very helpful. Thanks a lot!
Excellent demonstration.
Would it be possible for you to summarise this in bullet points please?
You HAVE a Uranium marble? Bloody hell, wicked! Where can I get one and how many pounds do I have to part with?
How is this safe? I hope you conducted this in a fume hood.
Don’t try this at home kids
@@PhysicsOnline Please don't try this again without the proper protection.
Some UV glasses are in order, too! A fine explanation nonetheless, thanks.
have you got a video for the entire summary of Quantum Physics like your mechanics video
Thank you !!!
Please make video on line spectrum..
I have!
Hi sir, I was wondering why the electrons go back to the ground state
They like to be in their lowest possible energy state
“They like”😂
趙佶 yeah, electrons have conscious minds.
Electrons tend towards the lowest possible energy state allowing them to be as stable as possible basically.
Mathew Philip why not? The electrons work hard and smile
i hope u r ok sir.
The coating on the inside of fluorescent light tubes absorbs ultraviolet light and subsequently emits visible light. An inventor claims that he is able to do the reverse process. Is the inventor’s claim possible?
hello, I really want your thought in this question...Thanks
sweet and clear explanation! loved it !!!!! but can you please tell me how is this fluorescent lamp related to self induction because it says that they are related in my text book and i just can't figure out how ?
a means to limit the current would help/
what is argon?
I wonder what's the purpose of the argon
inert gas, I guess it would work fine with mercury vapor only, but then it would require even lower vacuum which is already super high (check video from Photonicinduction watch?v=CrP3Y6u7RHs) they probably found out slightly decreased vacuum is still ok and its easier to manufacture...also its less likely to implode, due to lower pressure difference between vacuum inside and atmosferic pressure
why do the electrons go down energy levels to the ground state after atom has been ionised ?
I think that the concept is that they always want to return to their least excited state -but please verify this.
0:56 LMAO WHAT
wolololooh merci bien monsieur
When an electron absorbs enough energy to leave an Atom then what happens to that electron does it still emit that energy later?
@Huzzboy I believe this explanation should have been in video
Did you use a mask when breaking the tube? I've read we shouldn't inhale the mercury vapor inside the fluorescent tube.
The tube contains around 10 miligram of mercury....extremely small amount, if you dont do this every day, you'll be fine
sorry just a question ... the electrons are not only hitting the mercury attoms but they are also hitting the phosphor attoms too simultaneously .. what happens to those ?
I think that only the uv rays (produced from electrons striking the mercury) have sufficient energy to excite the phosphor and create fluorescence. The electrons produced by the filaments can't get the job done -to be verified.
Terrible lighting
not necessarily - with electronic ballast and high CRI tubes it could be actually quite nice lighting