Refraction & TIR - A-level & GCSE Physics (full version)

scienceshorts.net Please don't forget to leave a like if you found this helpful! ---------------------------------------
00:00 Refraction, refractive index & Snell's law
10:57 TIR - Total Internal Reflection
16:10 Optic fibres -
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[@joenash338]

Mate you’re seriously saving my physics a level thank you so much

[@sameerhussain3562]

what did u get in the exam

[@youthanki6188]

Sameer Hussain a C for Corona

[@officialcatchingair1932]

A level, what I’m doing this in year 8

[@PanzerSoldier]

Official CatchingAir topics are repeated and made much harder.

[@hayfordsarfo1646]

@@officialcatchingair1932 LMAO that means ur year 11 & a level content is going to be HEFTY

[@iSteelRazorBladeGAMING]

Just went on a marathon through all your AS topics. Safe to say you have me covered. Thanks.

[@alii7520]

SteelRazorBlade // AdamSRB Good Luck in your A2 exams

[@zidans4956]

SteelRazorBlade // AdamSRB how did it go? Were his videos enough revision?

[@zohaibgulawan9070]

@@zidans4956 where is was enough?

[@timothychinye6008]

Guys, no it's not "enough". If you want a good grade, your best is to revise all the topics, do a fk ton of past and practise papers and study the mark schemes... Only then are you likely to get a good grade. So, Science Shorts (and I guess; CGB Books, Physics Online, etc) will only get you a third of the way. You need to do the past & practise papers to get you familiar with the questions you'll probably be asked and how they want you to ask them, as well as the amount of time to spend on each questions, etc. And you need to study the mark schemes because, each exam board is different, e.g; acceleration of gravity is 9.8 ms^-1 for some exam boards and 9.81 ms^-1 for other (and 10 ms^-1 for some math exam boards). Most physics tutorials tend to go for the most common exam boards; Edexcel for Maths, AQA for Sciences so you need to make sure - even though physics is physics, you're answering the questions in a way that the Exam Boards want you to.

[@user-zc5fb5xn4y]

@@timothychinye6008 'enough' is basically what it means to pass, so yes you would pass with these videos.

[@joshvir262]

video number 4. 2 days before exam

[@arooshatariq5573]

nice

[@KGTKK]

Same!😂

[@yeety1208]

more like 2 hours 😂

[@deadshot3968]

I actually love you so much I was struggling so much with waves and now while watching your videos everything has clicked just 4 days before waves tests wish me luck and thank you. Currently have got 100% test in chemistry and 2 95%ish tests in maths, and now hopefully I get at least 75% in physics. (aiming for oxbridge )

[@noorahmadlondon]

damn this quote has power!

[@__maria2509]

did u get into oxbridge??

[@gecko2023]

something my physics taught me which is quite useful for remembering the light bending thing, FAST, fast away slow towards

[@gerardaslisauskas1217]

Best explanations so far out of any videos, thank you so much.

[@jolyonsage8616]

Where tf have u been my whole school career

[@sea5205]

Best channel for a level physics!

[@ea9814]

At 18:02 when he said 'red light green light', that hit different.

[@kaaruni]

lmao

[@puddleduck1405]

lmfaooo yeah

[@user-cl1fz1sc2c]

wait does this mean it's actually energy being refracted reflected and diffracted. Since a wave is an energy transfer.

[@georgedickson6550]

very good video! thank you very much. I should just mention that you probably shouldn't put exclamation marks after values or constants because it looks like you mean factorial. but its a perfect video and very useful

[@magn8195]

This helped so much!!

[@coffinman4527]

actually helped a ton! thanks!

[@v3lar110]

this is so good keep it up !!!!!

[@eyerusamber165]

Thank you this helped so much

[@jacllwyd5000]

How would I calculate the refractive index of the cladding?

[@hadishandai1182]

thanks very helpful tutorial

[@folbfolb]

How is his voice so deep in some videos compared to others

[@akirabalaba]

i know right

[@zeroitedono2547]

why for relative refractive index is 1n2=v1/v2=n2/n1?

[@steevoo]

How are pulses exactly stretched in multipath dispersion?

[@davidpacker7602]

light can start at the end of the cable at any angle, if it went straight down the middle of the cable it would arrive at the end earlier than light which started wonky and bounced of the sides multiple times meaning it had to travel a longer distance

[@naheemahakinwale8403]

At 8:38, you say light wants to get away from the normal but it is moving towards the normal?

[@7490maddie]

as in the faster light is going, the more it can get away from it like a race - this confused me too at first

[@hasty6809]

absolute legend

[@mahmudjahed7355]

can u make a video on Dispersion and btw your vids are super helpful

[@thedemongodvlogs7671]

Why is it m/s ‐¹ ?

[@Aly_jaf]

Subscribed

[@rayhanulchowdhury3560]

thanks mate

[@fizazaman8580]

You save my grades

[@justnarvi..]

Some plz help, 14:40 how did he get sin90 and then why did he just bar it off? :(

[@keranveermann9418]

The 90 degrees is the refractive angle, it travels along the boundary. So he used the equation n1sini = n2sinr he subbed in 90 which is r. Sin 90 on your calculator is equal to one so theres no need for it. Anything multiplied by one stays the same. I hope this helps please say if you got this or not.

[@justnarvi..]

@@keranveermann9418 thank you soooo much

[@PlainVlogs]

Can we used n=sinθ1/sinθ2 for materials which arent air? such as glass and water?

[@alialmeerahmed6994]

no

[@fellowmemer5693]

​@@alialmeerahmed6994yes you can? We literally can

[@lewismacpherson395]

What's the difference between multipath, modal and material dispersion? Thanks.

[@emilytaylor1781]

Modal and material dispersion are types of multi path dispersion Modal caused by light waves entering the fibre at different angles which causes pulse broadening as rays take diff times to reach the end of the fibre Material dispersion is when light wit diff wavelengths are used which means that the light rays will be travelling at diff speeds which also leads to pulse broadening

[@naheemahakinwale8403]

With the car illustration, you mean there is mor friction on grass not less friction right?

[@justinsankar1164]

Yea

[@adnansakeeb739]

No he meant less friction, thats why he said skid...

[@adrianjonsson2581]

amazing explanation

[@TinieTekkerzZ959]

Good luck AQA people tomorrow🤞🏻

[@ActuallyAudacity]

Thanks!

[@excelmaths4889]

Thank you !

[@arsal16]

how your paper went tho?

[@zeroitedono2547]

why is n1 sin theta 1= n2 sin theta 2 , you said something about substituting n=1 *(refractive index for air) but am still confused i understand the rest of this topic though.

[@emilytaylor1781]

The n1sinθ1=n2sinθ2 is snells law, there’s a whole massive derivation thingy that you don’t need to know for a level, n =1 for air as the we for refractive index is n = c(speed in vacuum)/ speed in medium so for air that’s 3*10^8 / 3*10^8 which is one

[@zeroitedono2547]

@@emilytaylor1781 thank you very much i overcomplicated it lol i thought he substituted n=1 into snells formula and it seemed confusing

[@imasha7315]

You’re a G

[@jfernandes_25]

Hi sir, I've done an exam question where you had to continue a ray after it hits cladding and it says it hits at the critical angle(2 marks) So I did a line at the boundary and got a mark however why is it you need to show reflection as it is not totally internally reflecting is it? Thank you. Edit: why do you need to show reflection for the second mark.

[@waleedoo]

sir I have a question, I did a multiple choice question where it said that a condition for total internal reflection to occur was that the wavelength in medium 2 must be bigger than in medium 1 , why is that?

[@samtaylor4680]

When light passes into another medium, the frequency always stays the same. For TIR light must pass from a more optically dense to a less optically dense material. higher RI -> lower RI. If the light passes from medium 1 to medium 2, the speed must increase. c=fλ , as f is constant, c is proportional to λ. So if there is to be TIR, light would have to travel faster in medium 2, which in turn means have a bigger wavelength (λ).

[@waleedoo]

Sam Taylor thanks 👍

[@samtaylor4680]

waleed hamad bit late of a reply, but hopefully that helps with exams just round the corner :)

[@geofreymhomela1618]

Nice video

[@fahad_hassan_92]

Mannnnnnnnnnnnn thanksssssssssssssss a lot

[@yuki002x]

is this even in the syllabus?

[@yuki002x]

@@ScienceShorts I mean A-levels 2024 syllabus?

[@Darkknight9035]

I think I just lost my mind

[@peterleveillee1321]

At 2:20 you say the light slows down and the frequency increases. That is not correct for going straight through the normal like the picture shows. It does slow down but the frequency stays the same.

[@ScienceShorts]

Did I say that though...? 🤔

[@peterleveillee1321]

@@ScienceShorts yes, "wavelength getting smaller"

[@ScienceShorts]

You said that I said "frequency increases" - I did not. I did say that wavelength decreases, because that is true.

[@_aidid]

Ads are annoying in this video

[@ScienceShorts]

3 skippable ads in a 20 minute video that you can watch for free?! *gasp*

[@justinsankar1164]

#rekt

[@CreamySun582]

>makes free content saving thousands of A-Levels >complains when 5 second ad appears Bruh

[@Munman-69]

shush