Total Internal Reflection & The Critical Angle, Optics - Physics

This physics video tutorial on optics provides a basic introduction into total internal reflection. It explains how to calculate the critical angle. If the incident angle is less than the critical angle, refraction will occur. If the incident angle equals the critical angle, the refracted angle will be 90 degrees. Total internal reflection occurs when the incident angle exceeds the critical angle.
Law of Reflection - Geometric Optics:
• Law of Reflection - Ge...
The Mirror Equation:
• Spherical Mirrors & Th...
Refraction of Light:
• Refraction of Light
Snell's Law & Index of Refraction:
• Snell's Law & Index of...
Total Internal Reflection & Critical Angle:
• Total Internal Reflect...
Thin Lens Equation:
• Thin Lens Equation, Op...
_____________________________
Ray Diagrams:
• Ray Diagrams
The Huygens Principle:
• Huygens Principle - Ph...
Young's Double Slit Experiment:
• Young's Double Slit Ex...
Single Slit Diffraction:
• Single Slit Diffractio...
Diffraction Grating Problems:
• Diffraction Grating Pr...
Polarization of Light Problems:
• Polarization of light ...
_________________________________
Final Exams and Video Playlists:
www.video-tutor.net/
Full-Length Videos and Worksheets:
/ collections

[@dragonartgroup6982]

With ur help I accepted in dental university entrance exam 😍thank u so much for all the things that u have done...

[@eieilovethis]

For the past 4 hours I’ve been waiting your videos. Thanks a lot my final exam is coming in a week. Your videos are helpful for me for maths, physics and chemistry. Again thank you so much.

[@ridafatima6021]

Thanks I found this helpful for a quick review.

[@BenardOnchieku-ny5qc]

I like your lectures.God bless you.

[@DapaChrons]

brilliant thanks

[@welln0w]

2:26 how do you know to associate 1 with water and 2 with air?? I paused the video and did it the opposite way around. Is it because the light travels from water to air?
I remember you said something about going from high to low, is that the application in this context?

[@RenDonut_glazed]

Yes. For total internal reflection to occur, the light ray has to travel from a material with a high index of refraction to a material with a lower index of refraction. Hope this helps

[@5z_07_bernicefonchinglam3]

hello, i’ve noticed that you said that total internal reflection wouldn’t occur if the angle of incidence is larger than the critical angle at the beginning of the video, but in the last example when the incident angle was larger than the critical angle you stated that total internal reflection will happen. could you please explain again?

[@dylanq8200]

my sac is tmrw and these vids to be saving me

[@NolwaziCele-dq4mf]

why you did not use 20 degrees in your calculation?

[@feliciaaderenleagbolade5435]

Wow

[@oyeladewisdom7971]

Pls how do u know whether the light will strike upwards or downwards

[@neokervinmabaso6743]

I noticed that in most questions, it will be specified where the light ray is coming from but when we're dealing with the critical angle or internal reflection then the light ray always comes from the material with a higher index of refraction (n) to the material with a lower index of refraction. e.g from water (n=1.33) to air (n=1) or from diamond (n=2.42) to glass (n=1.5). I hope I'm not too late and this clarified a little.

[@SalehSensei]

how do you know that the critical angle is equal, bigger, or smaller than the incidence angle??

[@dandanaka1273]

They wld give the incidence angle for eg qn 3 they gave incident angle 20°&35°

[@AnishK-go2ef]

[@BenardOnchieku-ny5qc]

If you were my high school teacher l could be somewhere else by now

[@GamerKrikt]

No more hey.😶