Collisions: Crash Course Physics #10

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  • Опубліковано 26 вер 2024
  • COLLISIONS! A big part of physics is understanding collisions and how they're not all the same. Mass, momentum, and many other things dictate how collisions can be unique. In this episode of Crash Course Physics, Shini sits down to lead us through an understanding of collisions. Plus, she brings along our old friend Sir Isaac Newton.
    --
    Produced in collaboration with PBS Digital Studios: / pbsdigitalstudios
    --
    Want to find Crash Course elsewhere on the internet?
    Facebook - / youtubecrashc. .
    Twitter - / thecrashcourse
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    CC Kids: / crashcoursekids

КОМЕНТАРІ • 596

  • @crashcourse
    @crashcourse  Рік тому +19

    We made quiz questions to help you review the content in this episode! Find them on the free Crash Course App!
    Download it here for Apple Devices: apple.co/3d4eyZo
    Download it here for Android Devices: bit.ly/3TW06aP

  • @aidanc7578
    @aidanc7578 8 років тому +752

    Hey Crash Course
    I was wondering if you guys could maybe start a series on music theory. It would be nice to have for musicians wanting to improve their work. It could cover topics such as chord progression, scales, Minor/Major...etc.
    If you read this comment please consider, and thanks for taking the time to read it. Keep up the good work.

    • @Shevzon
      @Shevzon 5 років тому +19

      Totally yes, same here i need music theory too.

    • @jaredcortes366
      @jaredcortes366 5 років тому +6

      Yes pleaseee!! I'm certain many people will benefit from this too!

    • @timandersson7372
      @timandersson7372 5 років тому +12

      There's a book called 'The Theory of Sound' by Baron J.W.S. Rayleigh and the first chapter of vol I is all about musical notes and the ratio relations between them. pdf available upon a googling and it's well interesting

    • @karleyv8180
      @karleyv8180 4 роки тому +5

      YES best idea I’ve ever heard on UA-cam

  • @ruhaanchopra8878
    @ruhaanchopra8878 5 років тому +150

    She speaks so flawlessly!! And clearly !!! She can simplify even the hardest of the topics !!!

  • @leeroyjenkins610
    @leeroyjenkins610 8 років тому +364

    How do I manage to hate school so much, yet still watch every Crash Course video?

    • @Matthew-lu4sf
      @Matthew-lu4sf 8 років тому +10

      No homework?

    • @maximusdizon7267
      @maximusdizon7267 8 років тому +4

      +Matthew Kessler but homework is important so we can apply what we learned.

    • @Skellborn
      @Skellborn 8 років тому +25

      You aren't forced to think too heavily about the topics at times you don't want to.

    • @pepegasadge2977
      @pepegasadge2977 8 років тому +12

      Because school offers so many boring physics topics and boring ways to learn them.

    • @VR_Wizard
      @VR_Wizard 8 років тому +10

      Try to ask your teachers questions about things you learned here at crash course and which you wanna learn more about.

  • @MrMineHeads.
    @MrMineHeads. 8 років тому +422

    Yes, yes.. mmhm
    I understand...
    some of these words

    • @piercehakola4085
      @piercehakola4085 6 років тому +3

      😂

    • @zub4516
      @zub4516 5 років тому +1

      I can pretty much relate...

    • @Vividlyvanilla
      @Vividlyvanilla 5 років тому +1

      i relate so much =D

    • @MrJayPuff
      @MrJayPuff 4 роки тому

      Just watch it like 4 times u’ll get it, dat what I did

  • @joshatwwc
    @joshatwwc 5 років тому +19

    Studying with UA-cam is easier than trying to sit through class. If I don't catch something I can always go back and rewatch it and better understand. Whereas in a classroom I'm left numb from not catching everything and hence don't learn a damned thing. Thank you for your videos they are much appreciated.

  • @X-3K
    @X-3K 8 років тому +374

    Speedy thing goes in, Speedy thing comes out.

    • @Amsirak88
      @Amsirak88 8 років тому +1

      👍

    • @Amsirak88
      @Amsirak88 8 років тому

      👍

    • @Kumaryoku
      @Kumaryoku 8 років тому +7

      You can't explain that!

    • @Arthera0
      @Arthera0 8 років тому +15

      ooh now I want to play portal 2 all over again. Don't help me procrastinate ;p.

    • @martinowong
      @martinowong 8 років тому +10

      i understand the portal reference, but I don't know why I first read this in cgp grey's voice

  • @tangerinesandvibes
    @tangerinesandvibes 5 років тому +158

    me: im going to read my barron's book for physics
    me instead: watches physics crash course while debating making brownies
    update: i made the brownies and will be giving them to my classmates tomorrow

  • @jasonl.n.williams9380
    @jasonl.n.williams9380 6 років тому +457

    This was uploaded...
    ...the day after my physics exam...

  • @gbizy
    @gbizy 8 років тому +864

    Collision Course Physics

    • @crashcourse
      @crashcourse  8 років тому +242

      How did this not occur to ANYONE else??? Hats off to you.
      -Nick J.

    • @ace_stealth251ace9
      @ace_stealth251ace9 8 років тому +5

      I do not understand can you please explain to me

    • @RockStar-gs1ik
      @RockStar-gs1ik 7 років тому +1

      The Commentator f

    • @ranshibuki9659
      @ranshibuki9659 7 років тому +1

      they should change the playlist name

    • @britterthecritter4531
      @britterthecritter4531 7 років тому +23

      crash = collision
      crash course = collision course

  • @alexflohr1453
    @alexflohr1453 8 років тому +10

    The day has finally come when CRASHCOURSE does a video on collisions!!! :)

  • @qianweijia1
    @qianweijia1 8 років тому +14

    This speaker has like the perfect voice for explaining things on the internet

  • @sharvanij2772
    @sharvanij2772 8 років тому +69

    This video helped me understand this concept just in time for the physics subject test this Saturday! All the love, crash course. xoxo

    • @crashcourse
      @crashcourse  8 років тому +11

      Woohoo!
      -Nick J.

    • @AldeyWP
      @AldeyWP 8 років тому +2

      Hey +CrashCourse, after this series is done, will you guys make a Crash Course about the Modern Physics (Quantum)? Pretty Please? I hope there's math too...

  • @ranshibuki9659
    @ranshibuki9659 7 років тому +140

    "every action has and equal and opposite reaction."
    -except when we both start rappin!-

    • @tadaiyoradima
      @tadaiyoradima 6 років тому +4

      mgk vs eminem

    • @shards4285
      @shards4285 5 років тому +6

      im satisfied with your pun, its non-stop. You have no idea how long i've waited for this.

    • @kolbeowen3052
      @kolbeowen3052 4 роки тому +5

      Isaac Newton v bill nye

    • @italobeltran1316
      @italobeltran1316 4 роки тому +3

      I’ve accelerated the mind of mankind

    • @ectoOLDACC
      @ectoOLDACC 4 роки тому +3

      The integral sec y dy from 0 to 1/6 of π is log to base e of √3 times the 64th power of what?

  • @DeadPyro96
    @DeadPyro96 8 років тому +6

    Another great episode! Seriously don't understand how people can find these incomprehensible. You can't dumb it down much more, if you actually want to learn something.

  • @val71999
    @val71999 5 років тому +7

    how is it that i can have a teacher tell me something for an entire semester but won't understand it until i watch a 10 minute crash course video? i'm killing this physics final today!

  • @larto42
    @larto42 8 років тому +11

    So beautiful gradients at the end! Great job as always graphics team :D

  • @ohthatsnot_
    @ohthatsnot_ 8 років тому +7

    Can't wait until we start discussing electricity and electric circuits! These physics episodes are the highlight of my Fridays :D

  • @mozayeniml
    @mozayeniml 7 років тому +87

    I honestly though she said a bag of bees rolling down a hill that would be easy to stop.
    NOTE DO NOT ATTEMPT TO STOP A BAG OF BEES WITH BEAR HANDS.

  • @saeedbaig4249
    @saeedbaig4249 7 років тому +2

    2:20 - 2:31 = U said impulse is the "integral of the net force on an object over time", but then added "in other words- it's change in momentum". I'm confused. I thought force was change momentum (d(mv)/dt). How can impulse, which is the integral of force, also be a measure of change in momentum?

  • @jedwardfanxox6
    @jedwardfanxox6 8 років тому +64

    yes queen

  • @tiuk23
    @tiuk23 8 років тому +6

    I'm literally in love with this host. She's the best one in teaching physics.

  • @DigiWorldOne
    @DigiWorldOne 8 років тому +19

    *"Momentum, the Product of Mass and Velocity is conserved between portals. In Laymen's terms, Speedy thing goes in, Speedy thing comes out."*

  • @MilesQuickster
    @MilesQuickster 6 років тому +45

    Perfectly inelastic?? UGH, ECONOMICS!

  • @janedoe4339
    @janedoe4339 7 років тому +1

    We have slow-comprehending brains (in that it takes our brain longer to translate what our ears are hearing) (autism) so the video "words" were too fast for us to comprehend but the photos / examples were GREAT!

  • @dennisdonutshovel6893
    @dennisdonutshovel6893 5 років тому +2

    The ball equation on when the ball hits the wall and changes its force in half a second. The equation itself was correct but the answer is 3.125. This is important for people taking the AP Physics C test, for they need you to round to the nearest 3 decimals.

  • @mineshnissanka7139
    @mineshnissanka7139 Рік тому +2

    Indiana Jones died just so we could learn about momentum. We must ace our physics tests to not let his death go in vain

  • @elipantoine
    @elipantoine 8 років тому +5

    I don't know who you are and I don't like the fact that you're not John or Hank Green but I will live with it since you have the most gorgeous accent I've ever heard

  • @Lee_yourboylee
    @Lee_yourboylee 8 років тому +5

    Enjoyed your contribution to the programme about the battle of jutland on the bbc, shini. Very interesting.
    Really liking CCP, too.

  • @microdavid7098
    @microdavid7098 5 років тому +2

    In Highschool, Kenya, we call it the Centre of Gravity, not mass. Not much of a difference, but it shows how different our curriculum is.

  • @TheFireflyGrave
    @TheFireflyGrave 8 років тому +3

    I"m surprised by how much I learned from this video.

  • @DracarmenWinterspring
    @DracarmenWinterspring 8 років тому +3

    7:40 more like 2/3 of the distance between the centers of the balls, not the stick (assuming the stick itself is massless). This might not be significant for a long enough stick and balanced balls, but it's significant when calculating a more skewed system. Like the center of mass of a solar system (which can be inside its star or very near its surface).

  • @4tytude
    @4tytude 4 роки тому +1

    thank you!!! thank you for helping me to find the joy of learning this! (instead of just memorizing useless formulas that I don't get where did those derive from!)

  • @kieranelson7754
    @kieranelson7754 7 років тому +6

    I was stressing so much about 9 mins and 20 seconds ago, these videos are such great review tools!!

  • @UkeNooberx333
    @UkeNooberx333 7 років тому +1

    shoutout to all the AP physics students who think they will understand all the concepts the night before the exam through crash course

  • @clementinerosette1038
    @clementinerosette1038 5 років тому +11

    Taking my physics final in like 7 minutes

  • @lowhertzhighspl
    @lowhertzhighspl 5 років тому +2

    Finally! A video I found an actual use for making legitimate use for UA-cam's slow-down feature rather than only making people sound drunk. 😁

  • @SuperHappyHater
    @SuperHappyHater 8 років тому +1

    I would really enjoy a series in which you guys talk about culturally significant music, from pop culture to the classics. I often feel like uncultured swine when a song comes on the radio that I don't know and everyone else seems to think it is iconic.

  • @whitemamba2049
    @whitemamba2049 8 років тому +34

    This lady is amazing. Wish she taught at my college. Would have done much better in Calculus and Physics in college and became a scientist instead of a lawyer . . . . plus she's got to be the best looking Physicist I've ever seen :-)

    • @user-nd1lx8co2g
      @user-nd1lx8co2g 6 років тому +2

      she's reading a script honestly I find her a bit distracting trying to prove a point about female physicists or something. THERE I SAID IT :P

    • @jasonkaufman2385
      @jasonkaufman2385 6 років тому

      she is ugly

    • @sarahholland5980
      @sarahholland5980 5 років тому +4

      @@user-nd1lx8co2g So just because a female has a career in STEM, she MUST be proving a point and furthering the feminist agenda instead of just pursuing something she's genuinely passionate about? Good to see misogyny is still alive and well.

    • @user-nd1lx8co2g
      @user-nd1lx8co2g 5 років тому

      no it's just that everything about this is fake she is reading from a script @@sarahholland5980

    • @sarahholland5980
      @sarahholland5980 5 років тому +1

      @@user-nd1lx8co2g But when Hank and John read from scripts it's no big deal right? They're not fake just because they're males? Okay, whatever you say.

  • @mechasentai
    @mechasentai 8 років тому

    Crash course is the best series ever.

  • @princejohn5723
    @princejohn5723 4 роки тому +2

    This is a great video!! Thank you!! Also love how the pool table scenes have that background noise. So creative!! Haha!!

  • @SamSClair
    @SamSClair 8 років тому +1

    Big love from everyone revising for M1 in England!!

  • @sandygehrmann6309
    @sandygehrmann6309 8 років тому +3

    My science test is on Tuesday... please finish the series before then!!!
    That would be amazing for my revision :)

  • @tobymanurung9717
    @tobymanurung9717 8 років тому +2

    what a helpful video!!! thanks for the knowledge crash course

  • @flamedragon07
    @flamedragon07 4 роки тому +1

    Love the Indiana Jones joke they used. Crash Course you're so amazing.

  • @frederickleo2748
    @frederickleo2748 8 років тому +1

    you said in your video on newton's laws that according to newton's first law, an object would remain stationary (or in constant movement) unless acted upon by a force. A moving object that has momentum is moving at a constant velocity and thus has no acceleration, ergo should not be able to exert a force. However, that rolling ball is obviously able to move indiana jones if it collides with him. How is that?

  • @abrahambrambila2465
    @abrahambrambila2465 8 років тому +32

    brains and beauty.

  • @iceeprincess1
    @iceeprincess1 4 роки тому

    I love this teacher so much

  • @stephendean2896
    @stephendean2896 4 роки тому

    I was hoping that it would be my favorite narrator when clicking this on the video. Luckily it was, which means my day is off to a good start

  • @evandiego2962
    @evandiego2962 7 років тому +1

    definitely gonna watch all ur vids this saturday lmao

  • @lifehack7271
    @lifehack7271 4 роки тому +1

    Good

  • @driss1808
    @driss1808 8 років тому

    So wait, force is the derivative of mass times velocity, a.K.a momentum relative to time. Mind Blown

  • @VyvienneEaux
    @VyvienneEaux 4 роки тому +1

    Is kinetic energy derived from the integral of momentum? 1/2 V^2 looks like an antiderivitive.

  • @leaselmary_sims2189
    @leaselmary_sims2189 8 років тому +3

    In Russian momentum is called "impulse" and "impulse" is called "force impulse". It got me confused at the beginning, because every time I hear "impulse" I think of the momentum.

  • @camilleandrea9262
    @camilleandrea9262 4 роки тому +1

    What's the difference between momentum and inertia?

  • @ozgeozcelik8921
    @ozgeozcelik8921 8 років тому +4

    Sir Newton, what a fascinating man

  • @WarzSchoolchild
    @WarzSchoolchild 7 років тому

    Linear Momentum and Angular Momentum are very similar both are 'Vector' quantities, except with 'Angular Momentum' the vector is constantly changing, there is only an 'instantaneous' vector at any particular subtended angle of rotation. Sir Isaac Newton was correct about 'Actions and Equal and Opposite Reactions", but only in simple cases. Sometimes the word 'Opposite' can be turned around. For example we have two parallel tracks, each with a truck in linear motion. They both collide simultaneously with two mirror image discs. ...and just like the linear experiment Momentum is conserved by transfer of linear kinetic energy via two mirror image 'Elastic Collisions' into equal 'mirror image' counter-rotational Angular Momentum. ...These discs are equipped with magnetic bounce mechanisms like the trucks, [near 100% elastic bounce] they bounce back and return their 'Angular Momentum; with a third 'magnetic bounce' to the pair of parallel track trucks. The trucks have effectively "Bounced Back", but it will be observed in practice and reality, that there has been no measurable reaction at all. If this experiment is conducted on a small toy boat, the boat will keep going forward with each elastic bounce, but never go backwards. "VECTORS! MATTER" and please never forget that essential face, especially with a' Vector Quantity' like Momentum.

  • @Kristine.baltazar
    @Kristine.baltazar 7 років тому

    These videos are so helpful and save so much time!

  • @WindImHaar
    @WindImHaar 8 років тому +2

    I really like this series, you are all doing a brilliant job on the topics, animation, presentation and so on :D Only thing is that she talks a bit slow but that's ok cause we have the 2x speed option ^^

    • @thegamingwhovian8247
      @thegamingwhovian8247 8 років тому +4

      That's the first time I've ever heard someone say that a crash course presenter talks too slowly

    • @nuclearwarfareaw
      @nuclearwarfareaw 8 років тому

      +TheGamingWhovian I said that too! Even 2x speed is too slow.

    • @ChimeraGilbert
      @ChimeraGilbert 8 років тому +1

      I wish they had a 10x speed but that probably still wouldn't be fast enough for me. If she's going too slow then you guys should probably move on to a video that's more involved because this is just a sliver of how involved physics can get.

  • @unknownpawner1994
    @unknownpawner1994 8 років тому

    Things are gonna spin right round baby right round like a record baby right round round round next week

  • @buenchiko007
    @buenchiko007 8 років тому

    woah, you uploading this right the before i have a test about collisions is amazing (for me)

  • @morrisc18
    @morrisc18 8 років тому +1

    Where does the 25 come from in the impulse equation at 2:44? I understand it is an integral over .5 seconds but where does 25 come from?

  • @noahmeroueh4983
    @noahmeroueh4983 6 років тому +1

    Could an elastic collision be possible in a vacuum, where heat and sound are impossible?

  • @mr.thophombenge492
    @mr.thophombenge492 5 років тому

    up to the par

  • @AyeshaKhan-gp9on
    @AyeshaKhan-gp9on 7 років тому +10

    If tendency of an object to remain in motion is called momentum, isn't it sorta similar to inertia??

    • @griseldamarku6060
      @griseldamarku6060 7 років тому +4

      Inertia is the tendency of an object to remain in motion or rest while momentum is the tendency of an object to remain in motion :)

    • @amineaboutalib
      @amineaboutalib 5 років тому

      think of momentum as a special case of inertia

    • @Ying-yang6969
      @Ying-yang6969 4 роки тому

      Momentum is inertia at a certain point when collision happens.

  • @sophiepeen2307
    @sophiepeen2307 8 років тому +2

    Can anybody please explain the math at 2:37? :)

  • @cristianrueda2055
    @cristianrueda2055 7 років тому +1

    I really love you :3

  • @pankhudisaraswat2445
    @pankhudisaraswat2445 7 років тому

    thanks

  • @jeromeeuler168
    @jeromeeuler168 8 років тому +1

    awesome episode!!!Very informative

  • @Lamplovr
    @Lamplovr 11 місяців тому

    Literally so helpful

  • @GAVISIONI
    @GAVISIONI 8 років тому +2

    Teachings technique is awesome

  • @NickDeBusk
    @NickDeBusk 8 років тому

    love it. thanks

  • @benheideveld4617
    @benheideveld4617 5 років тому

    Unique content! I found no better.

  • @arwildo
    @arwildo 8 років тому +6

    1:15, *F* = m(d *v* )/dt = m(d *a* t)/dt = m *a*

    • @akshat-kharbanda
      @akshat-kharbanda 7 років тому +1

      Arwildo thats only gonna work if a is constant

  • @emmycoffey400
    @emmycoffey400 7 років тому

    i owe you my life! these videos rock

  • @luchomolinari
    @luchomolinari Рік тому

    Hello there! May I know her name? I'm enjoying the course

  • @fernandomaron
    @fernandomaron 6 років тому

    thank you for the video!

  • @NDragon89
    @NDragon89 8 років тому

    Computer Science should be the next Crash Course

  • @MrBuddy5671
    @MrBuddy5671 8 років тому +1

    I want to see a crash course series on computer programming

  • @AlexE5250
    @AlexE5250 8 років тому +3

    Can elastic collisions occur in a vacuum? This seems to make sense because there aren't any particles to make friction. For example, if one object were to crash into a stationary object of equal mass, then all the energy should transfer into the stationary object and send it moving at the same speed as the first object was originally.

    • @animowany111
      @animowany111 8 років тому +1

      No - some energy is converted into heat. Sound is just one of the ways for energy to disperse.

    • @AlexE5250
      @AlexE5250 8 років тому

      +animowany111 but no energy is converted to heat because there is no friction. Right?

    • @animowany111
      @animowany111 8 років тому

      But there is compression, AKA sound within solid objects, or deformation, both of which turns into heat (try bending a spoon, it will get hot, it's internal friction between the molecules of metal in the spoon).
      And who said there is no friction? There might not be any with the vacuum, but between the objects, why not?

    • @AlexE5250
      @AlexE5250 8 років тому

      +animowany111 good point. Thanks for the explanation!

  • @johnnyace1300
    @johnnyace1300 4 роки тому +4

    I forgot how much she was my favorite HEY QUEEN!

  • @cavewallmedia
    @cavewallmedia 8 років тому

    Helpfull video, thanks for your work

  • @jlowe5589
    @jlowe5589 6 років тому

    Love u Crash course!

  • @Staciabailey14
    @Staciabailey14 8 років тому

    This might save my GPA thank you so much!!

  • @getknowledgeaboutmanything633
    @getknowledgeaboutmanything633 6 років тому

    Superb girl!!!!

  • @daninja265
    @daninja265 8 років тому

    Wish this had come out before my GCSE Physics exams.

  • @utkukaradag6394
    @utkukaradag6394 4 роки тому

    Epic 👌

  • @breadwinnner
    @breadwinnner 8 років тому

    If you could upload all the Electromagnetism material for this course before my exam next week, I'd be so happy.

  • @victormaxwellpeters9771
    @victormaxwellpeters9771 4 роки тому

    Dear Madam,
    There is a question which is iching my taughts since many days, that why speed of sound is constant??? Even though sound propagate by means of elastic collisions between molecules, speed of sound should depend upon the speed of molecules near the source of sound. Yes I have heard it already that molecule speed is directly proportion with the increase in pressure so the bulks module remains constant and hence the formula holds. But why then same phenomena is not observed in collision of two identical elastic balls, were the velocity of second ball depends upon the velocity of the first ball and hence the velocity of propagation of this collision also depended on the velocity of first.

  • @kenlam7111
    @kenlam7111 6 років тому

    My name is Jeff!! Rah!!!! Rah!!!!! Rah!!!! Too much fun times !!!! Love the figure of SIR ISSAC NEWTON!!

  • @natplanetary
    @natplanetary 6 років тому

    you have saved my life

  • @redricochet
    @redricochet 8 років тому

    Youre awesome!!!!!!!!!!

  • @tituszban
    @tituszban 8 років тому

    Well, I have a physics final tomorrow. I hope this will have some use.

  • @noryokusha3759
    @noryokusha3759 5 років тому +1

    Do we add the mass dist. products?

  • @nicolecalabrese8573
    @nicolecalabrese8573 7 років тому

    I love her

  • @Pfhorrest
    @Pfhorrest 8 років тому +1

    Something's a little off here. She says impulse is change in momentum over time, but that would be mv/t, which is the same thing as ma, which is just force. Impulse is mv/t^2, or ma/t, or force per time.

    • @Rhaegar19
      @Rhaegar19 8 років тому +1

      Impulse is *just* change in momentum, and it's force*time. It has the same units as momentum (kg*m/s). It's the amount of momentum lost or gained.
      *Force* is change in momentum over time (kg*m/s^2)

    • @Pfhorrest
      @Pfhorrest 8 років тому

      You're right, I was confusing impulse with jerk, which is acceleration per time. Force per time is equal to mass times jerk, and may or may not be called yank; I can't find a reliable source confirming that.

  • @swisstraeng
    @swisstraeng 8 років тому

    Like before watching, anyway we can only love physic!

  • @vwlz8637
    @vwlz8637 8 років тому

    You really should change the intro to a kind of crash course chemistry style

  • @raphaelbresselsmith5954
    @raphaelbresselsmith5954 8 років тому

    At 6:00 she states that the momentum is conserved but some kinetic energy is lost because the now stuck together magnets are traveling slower than the single magnet. Where did the kinetic energy go? I thought this was a perfectly inelastic collision in which--theoretically speaking--no energy is lost to thermal energy. If momentum is perfectly conserved, isn't kinetic energy also conserved since it equals 0.5mv^2? Am I misunderstanding something? Great video overall, thanks for posting!

    • @Morelloforever
      @Morelloforever 8 років тому

      Energy and momentum are different quantities! Momentum will always be conserved, whereas (kinetic) energy will often be lost. I understand your confusion though; the equations for momentum and kinetic energy look similar.

    • @Rhaegar19
      @Rhaegar19 8 років тому

      In elastic collisions, no energy is lost. In inelastic collisions, energy is *always* lost. For the magnets, most of that is sound, but also some heat. The mass goes up, the velocity goes down, and the momentum (mv) balances out, but energy weights velocity disproportionately (.5mv^2), so it's lost.

  • @nadianadeem8528
    @nadianadeem8528 6 років тому

    her voice is so perfect