Physics 11.2.1a Refraction

[rachana481]

@derekowens does this mean that the wavelength becomes shorter but the frequency remains same ??

[derekowens]

@rachana481 Yes, I believe that's correct. The speed slows, but the color (which is related to the frequency) remains the same, so that means the wavelength would have to change. Good thinking.

[rachana481]

@derekowens thanku :) u are a great teacher ! btw happy new year , sir ! :) :)

[RyynPettyfer]

Thank you so much. Light is the last chapter in this year's syllabus and my teacher had rushed when teaching this to get us ready for the exams so i didn't really understand the topic. Thanks again :)

[SwoodyPlaysWow]

OKay i have a question when this happens does the wave stay constant speed after it slows down from the refraction if it slows down does that mean we can stop light?

[derekowens]

@SwoodyPlaysWow  The light will slow down when it enters the material (glass, water, etc) and then it speeds back up when it comes out.

[HnJ0550]

I have a question... during refraction, in the glass, do the gaps between those waves get smaller than the ones in the air..?? pls help me :)

[derekowens]

@HnJ0550 I think so. I think the light slows down, and the waves get closer together, while the frequency remains the same.

[HnJ0550]

@derekowens Thank You !!

[stevenmarkgalway]

Brilliant, Credit were credits due

[jorgemariobb]

awesome, thank you so much

[Pradeep7638]

best



[GeoffieD]

This was a really helpful video, thank you!

[paulofighters]

seriously, I love science because it makes sense, and having someone explaining science like you do makes even more sense.

Well done mate! From Australia

[cdizzle609]

;) CHEERZ BEBZ!

[TwiddlyKnobs]

THANKYAH!:)

[LUCYCULful]

do the angle of refraction and angle of incidence have the same amount of degrees?

[derekowens]

@LUCYCULful No, the angles are not the same. When the light is reflected, the angles are the same, but when it is refracted, you calculate the angles using Snell's Law.

[skmuslimah]

Thank you so much, I have an exam today, and study leave is really worth it!

[TheGondal24]

awesome sir.....

[asob17]

you sir need a medal

[scuzzulus]

nice explanation thanks

[122lomelo]

thanks, that was helpful even though i took it long time ago but know i understand it much more

[122lomelo]

thanks, that was helpful

[FireBenderKwyna]

thanks! :D

[RobCardIV]

what if you could make the lazer only one photon wide.

half the photon would snag first?

half the photon would intersect later?

no?

seems like there must be some other reason to me, besides wave interception timing X_x.

what am i missing?

[91444161]

HI SJI GUYS FROM 326

[ALJONpaul04]

thanks

[zoeclare95]

what are some examples of refraction in everyday life? like looking through at the straw in the glass of water. does this work the same in your eye?

[PocketzZs]

wow I can't believe I've learned more from this video than from my useless teacher, why doesn't he teach us like this on the whiteboard!??!

[fernandatauros]

Does it bend because when it enters a new material the frequency changes that is why it bends (someone told me), is this right?

[derekowens]

My understanding is that is bends because the *speed* changes, not the frequency. I would guess that both the speed and the wavelength change, and that the frequency stays the same. Someone might correct me on that if I'm mistaken, though.

[cacho112605]

I'm taking the MCAT and this is so helpful thank you so much i like your videos better than the khanacademy because you explain stuff faster, and u look like already prepared before starting to record the video thank you so much

[MidnightRedemption]

I usually do "advance reading" via watching videos on youtube.

On school, my physics teacher and class president are having a argument with the class, especially this, for they can't explain it as neatly as you. While me on the back are holding my laughter while they are making some ruckus.

Be on my position, you will also laugh for their example are of the scale.

By the way, Good Job..!!

[camel747]

You are one of those rare people who can explain things exceptionally well. I'm trying to wrap my brain around gravitational lensing, and your wavefront explanation got me at least part of the way there: It doesn't matter whether light is slowed down by glass, water, or the fact that time around mass runs slower. In other words, light gets slowed down by time itself when it gets close to mass (like a star), and the light gets bent. Thanks!

[Watzgd1]

really good video, you're good at explaining and you make it sound simple. Really helped me.

[11dayandnight]

perfect :) that really helped me study-- you explain it better than my teacher :P

[youtubalisation]

eh can u answer my question how does the snell noe that is sine not cosine, tangent!

[derekowens]

Yes, and that is a very interesting question. Snell found his equation experimentally, and he himself was unable to provide an adequate proof. Descartes also attempted a proof of Snell's Law, and failed. It was twenty years later that Fermat was able to prove Snell's Law based on his principle of least time. This "least time" concept is equivalent to a minimal path problem in differential calculus. I have a solution, but it can't be easily typed in a comment like this.

[youtubalisation]

You can also use the analogy of the car to describe refraction in the light ray. When the car approaches sand at an angle, 1 wheel will slow down first, causing the car to swerve.

[derekowens]

Oh, Yeah! That's a great one. Thanks, and that will become part of my lecture when we get to that chapter this spring.

[hacksign000]

this video is amazing, all of your videos are, you saved me from my tests and exam on refraction :)

[FranceOnly]

This was good ! Thank you

[HeliosTG]

Your videos are boss.

[hacksign000]

thank yo u! I have been looking for this for a while !

[xfjjx]

helpful (: