Conservation of energy | Work and energy | Physics

Conservation of energy | Work and energy | Physics | Khan Academy

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16 жыл бұрын

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Using the law of conservation of energy to see how potential energy is converted into kinetic energy. Created by Sal Khan.
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Пікірлер: 332

@Nuhjeea 11 жыл бұрын

Love all your videos, but I wish you did slightly more complicated Physics examples! I'm in college and your calculus videos were very relevant and taught me a lot! Your physics videos definitely helps reinforce my knowledge but the examples are often much simpler than ones I have to tackle in class/exams, etc.

@A591m 4 жыл бұрын

because of these videos i'm gonna get an A on my exam bet

@ordinary.salsabil 2 жыл бұрын

Watching after 13 years is still good 👍

@jeevacation 5 жыл бұрын

this video is 11 years old........ feel old yet?

@HiltyC 5 жыл бұрын

I feel like this learning is somehow better than the "progressive education" that my school district provides, 𝐞𝐥𝐞𝐯𝐞𝐧 𝐲𝐞𝐚𝐫𝐬 𝐚𝐟𝐭𝐞𝐫 𝐭𝐡𝐢𝐬 𝐬𝐮𝐩𝐞𝐫𝐢𝐨𝐫 𝐞𝐱𝐩𝐥𝐚𝐧𝐚𝐭𝐢𝐨𝐧 𝐰𝐚𝐬 𝐫𝐞𝐜𝐨𝐫𝐝𝐞𝐝

@mariaahmed1695 3 жыл бұрын

I was 4

@anonymousejones8742 Жыл бұрын

It’s 14 now , this was released when I was born 😭

@lucass4827 3 ай бұрын

@@anonymousejones874216 now and we are the same age

@tannermiller5412 8 жыл бұрын

Thanks for the videos! I was really lost on my homework so I decided to look for help and this is exactly what I needed.

@uheartbeast 10 жыл бұрын

I love your vidoes! They are helping me so much.

@diaverna 6 жыл бұрын

HeartBeast Hello!!! I am a subbie :D

@Jhayca0930 11 жыл бұрын

i understand you better than my teacher...thank god your channel exist

@akhan7535 8 жыл бұрын

I honestly love Sal so much. Thank you!!! Wouldn't have gotten through class without your help

@abdullahbineid4963 8 жыл бұрын

even I dont speak English very well , I got it thanks a lot

@abdallababikir4473 5 жыл бұрын

تعلم انجليزي تستفيد

@AnimeTheorysReddit 4 жыл бұрын

stfu

@alisuri6637 4 жыл бұрын

Acha

@SamLesCreations 8 жыл бұрын

I LOST IT AT "IT CHANGES COLORS, TOO, AS IT FALLS!" OH MY GOSH 7:30

@orchoose 8 жыл бұрын

+Samara Lesage lol

@orchoose 8 жыл бұрын

UNIVERSAL GALAXY Depends on your definition of tracher,,, if it is someone who can pass knowledge in clear way, than he is a teacher, oposite to some ppl working in schools.

@everythingyouneed7778 6 жыл бұрын

gravity=9.8

@shirajummunira5511 6 жыл бұрын

Drama

@Peter_1986 6 жыл бұрын

+Lunar Moon The closest I have seen Sal come to a school teacher is probably when he has visited schools and answered questions from children during math classes. There are a few images like that on the Internet.

@SamRobertduty 16 жыл бұрын

You are very smart. I hope all lot of people learn from this video. I am in grade 10, doing physics 11 and I am trying to learn energy before the teacher gets to explain it. THANK YOU !!!!!

@zachcombs1288 10 жыл бұрын

Thanks so much man, I have an ETA this week and I never really understood this process. This helped me so much!

@joey93282 7 жыл бұрын

You made it so simple, and I'm able to apply this underlying knowledge to more complex problems. Thank you for helping me.

@taehpawgaw5590 7 жыл бұрын

You make physics so much easier and understandable. I am starting to like physics.

@conve4521 14 жыл бұрын

your a wonderful man. god bless your parents for creating you.

@zoolgarudaaa 9 жыл бұрын

Really improved my understanding on this topic!

@0dontspeak 13 жыл бұрын

His voice is soothing. And he's GREAT at teaching! I understood it so well.

@CCxWudz 3 жыл бұрын

This channel helped me pass my college physics class years ago. Thanks for all the knowledge

@jessynsiesi5443 Жыл бұрын

I finally understand the conservation of energy 🎉

@odefeoberabor7597 9 жыл бұрын

I love this. It was looking impossible in class, thanks so much man.

@richard_darwin 6 жыл бұрын

It's actually the simplest, yet most important law of physics

@adeshcobra7543 5 жыл бұрын

Lol normal lecturers complicates our lives 😂 😂 😂

@fahadalbalushi1602 7 жыл бұрын

U do not know how much u have helped me, the a lot

@Basic-Tron 7 ай бұрын

Great video man, thanks a lot!

@littledivergirl1105 11 жыл бұрын

if all the students that actually learnt from this didn't go to class anymore all the teacher would have no class. this makes so much more sense than in the 1.5hr class i have

@musicaldarpan629 3 жыл бұрын

Lol.. did you passed your exam 😁😁

@NationalPro 12 жыл бұрын

FASCINATING!

@SweetreatsbyGab 5 жыл бұрын

I missed class for a field trip today. You’re a life saver

@Ghost572 12 жыл бұрын

glad you showed that example of an icey slide! made it even better

@TheQupus 9 жыл бұрын

that speck left at is really bothering me...

@DogeFrom2014 9 жыл бұрын

Glad I'm not the only one who thinks that!

@malevip 9 жыл бұрын

I wanted to punch my screen!! It was so irritating to see that one dot!!!!

@KenzoKento 8 жыл бұрын

+TheQupus Same omg I actually had to leave the vid lol

@GioGziro95 8 жыл бұрын

#TeamOCD

@sueyboys5066 5 жыл бұрын

@marklee1194 10 жыл бұрын

Thank you so much for your help.

@SuperBounceFM 11 жыл бұрын

4:49 that orange dot is disturbing

@bladervinay 12 жыл бұрын

Great video as always from Mr Khan well explained

@amalshafernando7993 5 жыл бұрын

such a good teacher!

@The3nlightened0ne 13 жыл бұрын

I've never seen anything as beautiful as mathematics

@Peter_1986 6 жыл бұрын

I have always found vector fields and graphs of polar coordinates to be incredibly beautiful. Vector fields have some very complex symmetric patterns, and polar graphs sometimes look almost like flowers.

@alisuri6637 4 жыл бұрын

Because you have not seen me

@surajinsha665 6 жыл бұрын

i like that concept thanks sir

@MrSoundhunter 15 жыл бұрын

So good at explaining! Thanks Sal!

@musicaldarpan629 3 жыл бұрын

12 years ago 😁😁

@yalilboya 11 жыл бұрын

Thank you for the videos !

@Munbo44 10 жыл бұрын

You have saved my life. My friend and I have been trying to figure this out all week (teacher isn't there sometimes, and when he is we have work or something) and we have a quarterly test tomorrow. Thank you so much!! :D

@nirmitbatavia8192 6 жыл бұрын

Munbo44 all the best... Wait after 3 years. 😆😆😆

@mewying5184 3 жыл бұрын

@@nirmitbatavia8192 It's been three years now what

@bellaschmidt9079 8 жыл бұрын

Thank you!!

@megaericproductions8360 4 жыл бұрын

Wow this video actually taught me, unlike the one hour lecture I attended from a dweeb with a PHD

@Mahmood- 8 жыл бұрын

Very informative. thanks

@mayad9963 7 жыл бұрын

Thank god for khan academy !

@jenkudos 12 жыл бұрын

You explained it better than my lecturer ever could! Thank you :)

@alisuri6637 4 жыл бұрын

Your welcome

@shivavishnu9984 4 жыл бұрын

Thank you for your effort for teaching sir

@wombatpandaa9774 4 жыл бұрын

4:34 anybody else bothered by the left corner? XD

@gold_455 11 жыл бұрын

thank you so much !!!

@littledivergirl1105 11 жыл бұрын

this man is honest to god a pure genius!

@h5348227 13 жыл бұрын

your a life saver may allah give you a long life full of happines

@gasserhegazy1267 2 жыл бұрын

THIS IS SOO GOOD

@TheHiddenSupremacy 11 жыл бұрын

your content is actually perfect for IB

@Grandbox1992 10 жыл бұрын

Thanks a alot ...

@thebigdille 14 жыл бұрын

so much more understandable now

@aena_ 3 жыл бұрын

Very informative

@Dyanahhhful 8 жыл бұрын

Just want to let you know that you are AWESOME and HIGHLY APPRECIATED! :D

@aena_ 3 жыл бұрын

Thanks alot

@armyrule0111 16 жыл бұрын

thanks..easy to understand.

@musicaldarpan629 3 жыл бұрын

Did you passed your physics exam? 😁😂

@ishan0369 7 жыл бұрын

Great!!

@MrNintoku 9 жыл бұрын

I don't care about the topic, I just find his voice so soothing.

@chrisofnottingham 14 жыл бұрын

Another way to state the consequence of this approach is; whatever the shape of the path which the object takes on its journey, its speed at any particular height is always the same. It's a shame that friction messes things up but in the world idealised ice slopes and perfect roller coasters I think its a really fascinating outcome.

@PewDiesBro279 11 жыл бұрын

Thank you very much i wish you were my teacher!

@drorharush 16 жыл бұрын

Thank you.

@musicaldarpan629 3 жыл бұрын

I am feeling like I am time traveling in past while reading so old comments 😁😁

@aena_ 3 жыл бұрын

Very useful

@adamaqmal 12 жыл бұрын

God Bless uploader.

@keen125 6 жыл бұрын

Wow!

@abhishikthmatta366 7 жыл бұрын

really helpfull

@valgal6911 6 жыл бұрын

I ALWAYS LOVE your videos, you speak well and have exceptional penmanship. BUT in the last few videos I have watched you are using a thicker font which makes everything hard to read, follow and understand.. PLEASE go back the the thinner font when writing so that it is easier to follow along and read!! Thanks

@dialasaab972 10 жыл бұрын

can you explain the formula or P.E+K.E+U?. which is change on potential E and change in kinetic E added to change in internal energy? what does the internal energy change, and how to solve for it?

@musicaldarpan629 3 жыл бұрын

Did u passed your exam?😁😁

@ChristopherChibaite 11 жыл бұрын

GOOD WORK I LIKE IT

@taevy12 6 жыл бұрын

thank you sir, you are 100 times better than my professor :)

@thesovereignonion2283 5 жыл бұрын

is good thank you

@rm130 15 жыл бұрын

you make my life so much easier!

@alisuri6637 4 жыл бұрын

I told you not to take hard-core kode

@alifarzanehfar 12 жыл бұрын

Also, you should be able to do some of those calculations, assuming you know the ideal gas law and are familiar with integrals.

@rampriyadarshini 14 жыл бұрын

awesome

@lemonade_tara7429 2 жыл бұрын

I feel that it's actually not always true in the example of the object rolling down the hill as some of the GPE must have transferred to heat energy as well owing to the friction acting upon the object.

@richard_darwin 6 жыл бұрын

Uhhh... I found about 3 videos on KZfaq with over 100k Views that talked about the conservation of energy. This is bizarre. The law of energy conservation is by far the most important physical law. How are there not more videos on this?

@leenukes7418 6 жыл бұрын

Thanks bro

@jossell911 10 жыл бұрын

Thanks

@jilwanrahimi8987 9 жыл бұрын

Nice, don't get why people dislike your videos. Great work

@adriankhoury921 5 жыл бұрын

Thank you ☺️

@jewbinson 14 жыл бұрын

@TuningAnApple Yes. Energy is a scalar, not a vector.

@3Rton 14 жыл бұрын

@3Rton I am not totally sure if this is correct but supposing that we want to know when the energies are exactly same it should work right?

@mohammedrayyan7316 9 жыл бұрын

thnk u so much

@opmike343 14 жыл бұрын

I swear, ALL college professors should be required to watch Khanacademy and PatrickJMT's videos before every stepping foot into a classroom. Too many of those guys (while VERY intelligent) have forgotten, or never learned, how to "teach".

@musicaldarpan629 3 жыл бұрын

Hii after 10 years 😁😁

@jyothia6770 Жыл бұрын

this video is almost as old as me yet better than what my lecturer teaches

@AnonymousHuman2.0 3 жыл бұрын

This vid is almost as old as I am. The first people who watched this probably already got a 20k a month job.

@alifarzanehfar 12 жыл бұрын

It depends on the temperature of air. The reason a pendulum loses energy is that it collides with air molecules. The extra kinetic that is given to all those molecules is represented as heat. To calculate this, you can assume a block is moving in one direction at constant velocity.Depending on the area of the face of the block, it's momentum, air temperature (average velocity of air molecules) and pressure(how many there are) it can be calculated how much heat is given to the environment.

@VivianaDM 13 жыл бұрын

My physics final tomorrow is about this. Thank you so much for explaining it!

@musicaldarpan629 3 жыл бұрын

Hey.. did u pass your exam?? 😁😁

@whig3982 8 жыл бұрын

isn't there a zeno's paradox with the definition of "right before touching the ground"?

@Sutto3721 11 жыл бұрын

Previously he said it's assumed to be 10m/(s)^2 just for the sake of easy calculations. Gravity, however, differs from place to place (even on earth)...places such as the north pole will be much different. But usually as a constant (the level of physics we're doing) we have the average of gravity as 9.81m/s^2, for simplicity sake.

@nodu6202 3 жыл бұрын

at the bottom of the ramp wont it be converted to heat and sound energy too? so kinetic energy wont be exactly 100j right?

@kurama5874 6 жыл бұрын

write clear !!!

@PandaPornography 12 жыл бұрын

how would you do this with kinematics??

@JazzoFett 12 жыл бұрын

THAT MARK AT 4:50 BOTTOM LEFT IS KILLING ME.

@pyLz 14 жыл бұрын

Nice video, but I wonder to what extent the conservation of momentum is affecting your result (the slope is being pushed to the left).

@ibda3color 9 жыл бұрын

Amazing , you saved me : )

@alisuri6637 4 жыл бұрын

Tu maut ke kuain me girnay wala tha

@annc6152 5 жыл бұрын

i love you. so much.

@TuningAnApple 14 жыл бұрын

@PeaceFighter2 I might be wrong, but calculate when the ball is at the peak of its trajectory (where the velocity is 0), and at that point find the distance of the peak from the ground (or bottom of cliff, where ever it's landing). With that you can calculate gravitational pot. energy. Then you can set initial potential energy + Kinetic energy equal to final potential + Kinetic energy and solve. At that point of energy you can use Energy = work = force x d and find distance. Force being mg.

@bisharalol 13 жыл бұрын

"I WILL SEE YOU IN THE NEXT VIDEO" *you never actually see us :( *

@malkisehgal2481 4 жыл бұрын

Hi there. How are you 10 years later!?

@siyayas9134 4 жыл бұрын

@@malkisehgal2481 hey there how are u 4 months later

@jerryd2243 4 жыл бұрын

@@siyayas9134 hey there how are u 2 days later

@comicbest2662 4 жыл бұрын

1month later😎

@musicaldarpan629 3 жыл бұрын

@@comicbest2662 9 months later 😁

@shaguftanoreen4472 7 жыл бұрын

good

@honeypot11 15 жыл бұрын

i just wanted to say thank-you for putting the time to make these videos for us. I think that you sound better than my physics teacher! lol and i laugh a bit at the little jokes you do xD and the shaky mouse sometimes (yes im weird) thanks again!

@musicaldarpan629 3 жыл бұрын

Heyy.. did u passed your exam?😁😁