Geometric Optics: Crash Course Physics #38
ฝัง
- เผยแพร่เมื่อ 4 ส.ค. 2024
- LIGHT! Let's talk about it today. Sunlight, moonlight, torchlight, and flashlight. They all come from different places, but they’re the very same thing: light! It’s what makes it possible for us to see the world around us, so it’s worth a close, hard look. For instance, how does light travel? When you flip that switch in the bathroom to brush your teeth, how does light move from the light bulb, to the mirror, and into your eyes?
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WE NEED CRASH COURSE MATHS
Angelo Thavaratnarajah I second this!!
U goddamn right
3blue1brown in the mean time
Try searching for the youtube channel y mx+c
The guy teach malaysian math but i think it will still teach you something
Btw he speak english
Two helpful hints: Watch with captions and at 0.75x speed.
And pause often to think if needed.
Thank you
1.5 speed with no captions: Badass mode
@@owencoukell388 Ur cool but I don't wanna fail my exam lol
@@owencoukell388 ok
That doesnt really help apart from the pause often part
I sometimes watch the videos twice... The first time I just listen and get what I can get, which usually is a broad idea of what the topic is about, then watch it again the second time while concentrating, pausing, contemplating and taking screenshots as necessary
Why do everyone complain about the speed of her speech? All crash-course videos are like this, it's the whole point to squeeze a bunch of information into a short video.
But it's not possible. People who don't know can't get this so fast
exactly, at least it's not boring as a 3-hour class, and it's the same data but faster and more simplified
Oh come on friends... You can slow down the video by yourself ...
I also felt that it's too fast, but there's way to solve the issue.... They are really doing a good work.
@@symbolofpeace.3846 i definitely agree with you. it's best to fix the problem by fixing ourselves, rather than blame others. crashcourse does really put in a lot of effort, and we should appreciate it, rather than complaining
She was wrong that the image is always upside down for converging/convex lenses. If the object is closer than the focal point, you will end up with a vitual image that is upright.
🖒
Periodt
Yeah
I personally struggle with holding thoughts more than 15 to 20 seconds at a time. The quick pace of this series is just right to hold my attention, and I feel the amount of information is just right. I have sat through these traditional courses, and after waiting for people who don't understand to ask all their questions I am already thinking of something else other than the subject matter. Thank you crash course.
If you struggle with following along at her natural speed (to make an information packed short video), I recommend choosing the 75% speed option. It is still relatively quick but much easier to follow along with for those of us that aren't as fast of auditory learners! :)
When you got a science test next and didn’t understand anything in class
If only more ants had umbrellas.
+
Dark Night of the Soul now I understand I was an evil kid
Dark Night of the Soul I.
I did that with other bugs. I wish other bugs had umbrellas too.
I learned and easily consumed more knowledge from this 10 minute video than I did in a week's worth of intense focus towards this exact subject in science class.
Why do I even watch these I can only follow them for the first 3 minutes
Pause button. Notebook.
I know cause they are thrash
Slow down and/or repeat
@@kurtpace1545 no u
@@kurtpace1545 they'r not!😭iam surviving high school! thanks to crash course.
The Star Wars reference was awesome.
+
I'm so glad this channel exists. It's the only thing apart from my dad keeping me from failing physics.
Thank you for giving the ant an umbrella
1:16 Last Jedi prophecy!!! They knew🤔
I love the Rogue One reference :D
Love it!!! We cover this in Physics 223 but in great detail. Great review!! THANKS!! Keep them coming please!
I agree. I love the Rogue One and the Last Jedi Prophecy references. Keep up the wonderful work. Yes, I wish they had Crash Course Math also. I could use the math help.
You know you've watched too much CrashCourse when you recognize that the animation is Scout Finch.
Great video! Such videos are extremely important to me, as my school teacher is useless 😂 We this I finally got to understand reflection. Very helpful! 😊❤
This video alone got me through grade 10 optics! Thank you so much crash course!
OMG I thought that robot was wacking it for a sec. 0:56
lol
Dylan T u have a dirty mind
@Idon'tgiveafuckaboutanythingH Lol u have it too...xD
SAME
it’s K2SO!
great! all your videos are so clear and useful!
THANK YOU THIS HAS HELPED ME IMMENSELY
This video has taught me more than the hours worth of lectures I attended for this part of Physics lol, channel never fails
I have been waiting for this topic for one year!
Turning a blurry world into a high-definition experience... yep, very much an accurate summary of my experience each time I update my spectacle prescription.
Great video! I have a physics exam tomorrow and i just not into reading tonight, and thought that this video explain almost everything from my text book! Greater ways to study,
P/s : read that some people thought that the teacher is talking too fast. I think that's not a problem though, some people need to study in a fast way, so they need to make a video no longer than 10 minutes. For those who can't catch up what she is saying (which happens to me too) I recommend you guys to pause the video to digest all of the information in your mind before moving on to another new information.
Have a great day ! ♡
And the animation is so cute!
You guys are amazing this video helped me alot with my physics exam!!!
I like this show. Keep it coming lol... Although I've already done lots of this stuff lol
This was exactly what I was looking for!
I love listening to you 😍😍😍 so much to learn 😍😍😍
really helped me understand! thanks x
i had to watch this on my online class 😭
Im doing that now :)
Awesome job!
Thank you so much, this really helps me.
They just had to use the rogue one reference which made my night 😂😂😂
This was the first crash course physics video I could keep up with first go
That unfinished 5x5 always distracts me ( the cube, ppl)
The whole point of "Crash Course" is that it is presented in a "crash" of information. The whole reason why it works is as a supplement to proper lectures, or with liberal use of either the pause button, or the replay button. This has been true since the beginning of this channel. - verdatum
I LOVED THE MIRROR MASTER REFERENCE!
CRASH COURse MATH PLEASE 😢😢
now that we have CS , MATH NEXT!!😣
...btw, thank you for CS 😊
Crash course is my favourite channel 😍😍😍😍
0:21 Love the Mirror Master appearance.
great explanation!
Thanks so much 💙
great video! :D
This is very helpful thank you
Really informative video!!!!!!!!!!!!!
5:23 focal length of lens depends on refractive index also ... the relation given there is that of a mirror.
Bombed my first optics test so I'm here XD thank u
You did very good!
So helpful for revise 🤗🤗thank u
cc is a life saver
I've never tried noticed that straw illusion, one day I'll have to give it a try... maybe right now.
now I'm wondering if optometrists know as much physics as engineers...
I was thinking the same thing! They must know something about all of the lenses they switch in front of my eye. Probably not as much as engineers, but they must know stuff about light and lenses.
Optometrists do have to take physics! They then specialize differently than engineers.
Wish I'd had this resource when I was first learning this :*D
A good thing to start a day
she has a good pronounce in English
and we have to slow the speed to understand it
actually the correct pronounciation make it difficult for me but still i can understand the way of teaching.
and i can understand everything about light in this video
Thanks!
Thank you so much for this video, it helped me a lot! But it would be better if it was a little bit slower because it was kind of difficult for me. Otherwise the video is good.
Have a nice day !
Exam in two days, this is on it and this really helps Thanks.
Thank you so much... You saved my life... Wonder Woman 😍😍😍😍
She is a wonderful teacher that makes the topic very clear.... She is flawless..... Love crash course physics because of her. Thanks
Appreciate, I have an astigmatism. Thanks.
The angle is the result of crying, then a promise. Side rear mirrors are based on this theorem.
Will you guys do an episode about shadows and darkness ?
I loved the Mirror Master reference
0:47 is looking more likely every day
Awesome
The infinite Rey pun has so much more meaning now !
had a test about this last monday. wouldve been really helpful :(
aw
exams lul
Thank you Very much Mam😊😊😊
Do you have any videos about convex and concave mirrors?
You guys should do a series on marketing ... Great vids
At 7:02 you stated that convex lenses always create upside down images. But don't they create erect ones if the object is with a focal length of the lens?
You Saved my Literally
hang on, doesn't convex lens form a virtual image when the object is placed between focus and pole?
I'm soooooooooo glad that Shini went slow this time. In the videos on electricity, magnetism, electromagnetism and Maxwell's equations, all she did was show equations at a breakneck speed.
This video taught me more than my physics professor in a month
want a lesson for separation of compound in mixtures
and composition of a mixture
umm....isnt the magnification for lenses v/u instead of -v/u in general...
also i think the sign in the lens formula is wrong.
What’s good is that you can go back and listen again if you get distracted compared to skl Lol.
CrashCourse should do a Crash Course to how you make Crash Course.
i got lost at reflection and refraction when its already like my third time learning and two exams of that topic
Isn't it a concave mirror is the converging lens while the convex the diverging? I'm confused.
Cool!!!
Hate to be that guy, but you really have a special ability to explain a relatively simple concept in the most confusing way possible. If your audience includes people who do not know what refraction is, then speeding through the sentence "this phenomenon of light rays changing direction at the interface between media" is going to leave them clueless. I know the point of this channel is to teach quickly, hence "crash course", but you aren't teaching at all when you talk like that. Just some advice from a teacher. Peace.
FWIW, it's REALLY hard to write something that's compact and makes perfect sense to all audiences on the first viewing. And this is especially true in the realm of physics. I think that's part of why the viewcounts on CC Physics tend to be particularly low. I often try to think of how I could write a better episode on the topics, and yeah, it ain't easy.
Following Feynman Of course, this is meant to _supplement_ a physics class, not necessarily replace it.
Legend Length: the problem is that before your brain has processed the information in this sentence, the presenter is far into the next sentence. The natural pause between the sentences, whatever originally was there, has been edited out to speed it up even further. It is speeding through complex sentences which is the problem, not the complex sentence in itself.
Following Feynman c
Following Feynman I agree, this has made it less enjoyable , she just seems to be speaking , not teaching...I needed help with my exams , but that didn't work out well I guess 😖
What my teacher couldn’t do in ten weeks, crash course did in less than ten minutes
Thank you very much. There are some of them 1; 17; 15; 25 I want the rest of the episodes translated into Arabic.
"Sunlight, moonlight, torchlight, and flashlight. They all come from different places, but they're all the very same thing."
Actually, both sunlight and moonlight have the same source. The only reason the moon "shines" at night is because it's reflecting sunlight.
KingsleyIII ?????????
Actually you all have it wrong, the only thing that makes anything shine is God because God made light
Oh sam smith, you're so silly. We're just talking about real things here, not fantasy fiction.
We were all born into a world without reason and our understanding of it through science although brilliant will always be fiction, how do we know the world is not being held up by a stack of tortoises. Being a scientist with no views on God or the nature of reality is refreshing, because people will generally cut others down for beliefs, but God is no more fictitious than science. Just think for a second you were born in a world that does not need to make sense , why would it. So how about we all stop thinking one way is right because we are all wrong no matter how objective you try to be
This is not about being right or wrong in the sense that you are stating. It's about being able to make _and share_ observations. The religious experience is, by its very nature, entirely private. We don't have precise words to make sure we are really talking about the same things, or even close enough. And that's fine.
With the scientific method and a scientifically accurate vocabulary, we can make sure that we are indeed talking about the same things, or at least that we are doing so as much as is humanly possible, which must suffice. You could say that such a method leaves out a whole lot of human experiences - such as the religious experience. You're right, it does. That's why science doesn't deal with proving or disproving the existence of deities - it's outside of its scope, for the very simple reason that these entities are not well-defined in a scientific way.
So we know the world is not held up by a stack of tortoises because: a) this has never been observed, either directly or indirectly; *and* b) every other observation, confirmed and confirmed again, contradicts such a hypothesis. With both those conditions, together, we can be sure. This is what being objective _means_.
So, how do you calculate "Dioptre"?
Generalized Yang-Mills Theory: Crash Course Physics #7,212
when?
Is there a mistake at 3:15? Says the higher the index of refraction the smaller the angle, shows the opposite.
i cannot see far that good, so I need glasses. when i watch to far away via mirror near me, why isnt the image clear? as light comes from reflection on mirror
Nice voice good vid
nice
Anyone here during stay home stay safe campaign pandemic with zoom classes, press like
So, I'm near-sighted, and effectively only see a virtual world... at least more than 6 inches from my face. How bizarre.
Do nọt like the speaker's way. Crazy