Center of mass | Impacts and linear momentum | Physics | Khan Academy

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  • Опубликовано: 3 мар 2008
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Комментарии • 268

  • @stokes111111
    @stokes111111 10 лет назад +116

    yo im freaking dying at homie tryna jump over the bar rn. neck broke and hes got 3 feet tho.

  • @shamimahmed7322
    @shamimahmed7322 6 лет назад +64

    Was he about to show an example of throwing a horse around its center of mass?

    • @gpgp
      @gpgp 2 года назад

      nope.

  • @itsMinuteMaid
    @itsMinuteMaid 12 лет назад +98

    22 pound rulers and horses that look like baby elephants. Man physics is confusing

  • @guitaromania1345
    @guitaromania1345 10 лет назад +94

    How does he know everything? All I know is the subject of what I'm studying right now

    • @KingDeramo
      @KingDeramo 10 лет назад +32

      Mythbusters are not the only ones with a team of researchers and script writers.

    • @8506goalie
      @8506goalie 6 лет назад +24

      That sentence taught me two shocking things

    • @BreakTheBeat852
      @BreakTheBeat852 5 лет назад +11

      I’m guessing you’re studying a lot of subjects, later on you can specialize on one specific subject of your choice, hopefully. That’s what these people do, they specialize on one subject and learn as much as they can about it

    • @ash.toronto31
      @ash.toronto31 4 года назад +3

      Yes once you do a pHD in science you will know all this too.

    • @aldreivohnaquino3100
      @aldreivohnaquino3100 3 года назад +3

      Uhm, Sal doesn’t just extraordinarily teach science guys, check the other playlists haha

  • @AhmedMahmoud-qv4bw
    @AhmedMahmoud-qv4bw Год назад +24

    hello is there any one alive here ?

  • @Bringmeoneofthosechickens
    @Bringmeoneofthosechickens 12 лет назад +6

    As a Knife Catcher. I found this video very helpful!

  • @1992Dadi
    @1992Dadi 7 лет назад +2

    Really cool example in the end !!!!! A nice presentation too !!!!

  • @shinobix4925
    @shinobix4925 5 лет назад +6

    Every day applications like high jumping

  • @tasneemferdoustahmeed8091
    @tasneemferdoustahmeed8091 2 года назад +1

    After even 13 years this is helping!

  • @jayaich7315
    @jayaich7315 5 лет назад +8

    That's a lovely horse XD

  • @turcugeorge5874
    @turcugeorge5874 8 лет назад +4

    Everyday applications like high jumping! that made my evening

  • @kaleab27
    @kaleab27 4 года назад +1

    I really loved the last example
    Thanks

  • @musicaldarpan629
    @musicaldarpan629 3 года назад +4

    4:50 sir discovered a new generation of animal on earth 😂😂

  • @sakerochting
    @sakerochting 8 лет назад +4

    Awesome, funny and logical!

  • @dejesuscassandra6386
    @dejesuscassandra6386 3 года назад +2

    uhhhh, Can someone explain what happened at the last example? why is the center of mass below the bar?

  • @jarikexe
    @jarikexe 8 лет назад +1

    The picture of high jumper is awesome !!!

  • @AnimeTeikoku
    @AnimeTeikoku 11 лет назад +3

    three take-aways:
    1. center of mass
    2. it's illegal for olympic bar jumpers to take drugs, but it's legal for them to have three feet
    3. I am 7 and a half rulers heavy...

  • @rushilpatel7418
    @rushilpatel7418 3 года назад +7

    Perfectly balanced, as all things should be

  • @SanityFairs
    @SanityFairs 10 лет назад +21

    THE HORSE. hahaha

  • @shreyasm3140
    @shreyasm3140 8 лет назад +1

    You saved me!! Thanks for your amazing video

  • @shivambansal99
    @shivambansal99 9 лет назад

    awesome video :D last example was great !

  • @boeing747200lr
    @boeing747200lr 13 лет назад +17

    Sal, you continue to amaze me!! Thank you. That high jump example was really awesome.

    • @AdityaGupta0130
      @AdityaGupta0130 Год назад +5

      What are you doing now for your job? I am seeing comment in 2022

    • @opiumCARTI00
      @opiumCARTI00 8 месяцев назад

      @@AdityaGupta0130probably in the field of engineering aircrafts if he really stood by that name

  • @moriahhamilton7436
    @moriahhamilton7436 6 лет назад +1

    thos drawings are hysterical.....understood the concept too

  • @organicjuice
    @organicjuice 7 лет назад +40

    That's not a horse.

  • @netadosalazar
    @netadosalazar 11 лет назад +12

    Thank you so much for doing this. I can actually understand physics now :)
    You do a wonderful job!

    • @raghidhammoud
      @raghidhammoud 6 месяцев назад

      are you still understanding physics?

  • @yasmeenkhan8803
    @yasmeenkhan8803 8 лет назад +3

    Thanx sal khan........for the awesome explanation ........

  • @abigailohara4560
    @abigailohara4560 Год назад +1

    Beautiful horse, thank you Sal.

  • @survs21
    @survs21 10 лет назад

    Thanks, I wish you taught me physics and calculus in varsity.

  • @emirselman3984
    @emirselman3984 7 лет назад +3

    How can the center of mass be distinct from the person...?

  • @LilTeresa101
    @LilTeresa101 10 лет назад +4

    Real life applications for the win! Learn something new everyday :P

  • @MizzRiverP
    @MizzRiverP 9 лет назад

    so helpful thank you!

  • @michaelthompson7217
    @michaelthompson7217 7 лет назад +21

    All praise afro horse

  • @AbdulRahman-pr4vo
    @AbdulRahman-pr4vo 3 года назад +4

    Im watching this 13 years later 😂

  • @HAWXLEADER
    @HAWXLEADER 12 лет назад

    THOUSANDS OF GREAT VIDEOS!

  • @DerMacDuff
    @DerMacDuff 12 лет назад +3

    DAMN AWESOME SQUARE !!!! and of course awesome videos :) thank you very much

  • @hannakozak3384
    @hannakozak3384 8 лет назад +1

    Thank you very much! :)

  • @serene9532
    @serene9532 6 лет назад +2

    6:42 😂😂😂😂 "I don't recommend that you do"

  • @sulaimanahsan6651
    @sulaimanahsan6651 7 лет назад +1

    If the force is not at centre of mass than what we can do..can we use parallel axis thrm..?

  • @user-rs5et1gs2r
    @user-rs5et1gs2r Год назад

    Thanks sir, appreciate it

  • @killmaster398
    @killmaster398 12 лет назад

    Thanks man my class is building bottle rockets and I had to find out how to keep it moving straight

  • @awesomemantroll1088
    @awesomemantroll1088 2 года назад

    This video is so old he said "I will now do a presentation on the center of mass," and he stuttered so much!
    Who knew some dude drawing on a digital blackboard would get so big?

  • @BangMaster96
    @BangMaster96 7 лет назад

    Sir you are just great

  • @johnkim96
    @johnkim96 11 лет назад +1

    Orange Styrofoam and Green lead. Makes perfect sense! ;-)

  • @stokes111111
    @stokes111111 11 лет назад

    excellent as always

  • @shirleyfan5232
    @shirleyfan5232 6 лет назад +1

    I thought Mr. Sal knows everything, now I know maybe he is not so good at drawing horses LOL

  • @abhijeetas7886
    @abhijeetas7886 4 года назад +3

    5:42. I dont know why i even drew the horse

  • @mahrezaitm.5162
    @mahrezaitm.5162 Год назад

    Thanks very much !

  • @quantumsystems9382
    @quantumsystems9382 10 лет назад

    lol, 'if youre a knife catcher, which you should consider" haha

  • @blackcharizard09
    @blackcharizard09 13 лет назад +3

    good job your video's are so educational that we have to watch this for homework in physics

    • @kadakmketema
      @kadakmketema Год назад +1

      12 yrs wow

    • @blackcharizard09
      @blackcharizard09 Год назад

      @@kadakmketema i know right! Which means that’s how long it’s been since I was a senior in high school

    • @kadakmketema
      @kadakmketema Год назад

      I just wonder

  • @swarnagirishbennur9159
    @swarnagirishbennur9159 6 лет назад

    I wish u could have explained a problem or two

  • @seemapandey9227
    @seemapandey9227 Год назад

    Amazing!

  • @wildbanana5628
    @wildbanana5628 7 лет назад +12

    3:22, Illuminati confirmed.

  • @iamnormalandcanbetrusted
    @iamnormalandcanbetrusted 6 лет назад +24

    Jesus Christ the dudes foot split in half

    • @cheesywiz9443
      @cheesywiz9443 6 лет назад

      HAHAHAHAHAHAHAHAHAHAHAHAAHAHAH xDDDD I was thinking the same xDD

  • @HAWXLEADER
    @HAWXLEADER 12 лет назад

    Just amplifying your point...

  • @debopriyapalit-me2516
    @debopriyapalit-me2516 5 лет назад +5

    I have a question how to consider friction in a centre of mass???

  • @jamienewman1488
    @jamienewman1488 2 года назад

    I didn’t quite understand why having centre of mass below the bar allows for higher jumps with the same effort?

  • @nrazdan8
    @nrazdan8 11 лет назад

    Before he started drawing a bar, did anyone else imagine the other type of bar and think "yessss this is the best life application example ever!"

  • @eXtremeDR
    @eXtremeDR 10 лет назад +4

    Awesome illustrations ^^ Ever heard about mass transfer with the gyroscopic effect? The center of mass can be transferred to any point - even to a point outside of the mass itself.

    • @Xzxzkanal
      @Xzxzkanal 10 лет назад

      How? and could this be made to a new propulsion system?

    • @L9X
      @L9X 8 лет назад +1

      +Quantum no, sadly not, this is a common suggestion upon people who are introduced to this phenomenon, but to create propulsion from altering the centre of mass requires you continuously move the centre of mass further and further away, so if you consider a rocket in a closed system, the fumes expelled from the rocket will push the systems centre of mass away from the rocket's body. So, in a way, it already is a propulsion system utilised by rockets and aeroplanes.

  • @aka3673
    @aka3673 Год назад +3

    Wow man 15 years at 240p

  • @_xerox_8779
    @_xerox_8779 8 лет назад

    illumenati confirmed XD but thanks that really helped me

  • @MrJongjongz
    @MrJongjongz 13 лет назад

    nice... ahm,, can you help me in my statics of rigid bodies subject>?

  • @bluepanda2808
    @bluepanda2808 4 года назад

    Thank you Sal...

  • @marcwittkowski5146
    @marcwittkowski5146 5 лет назад +1

    The most beautiful horse I have ever seen.

  • @oneofthem7992
    @oneofthem7992 5 лет назад

    Now I understand how " pen spinning " works !!

  • @luongmaihunggia
    @luongmaihunggia 6 лет назад +1

    That is a very heavy ruler.

  • @pawpawbear1175
    @pawpawbear1175 7 лет назад +65

    lol that was a horse?? hhahaha

  • @jnp4825
    @jnp4825 15 лет назад +1

    you drawings are very entertaining thanks for the help :D

    • @musicaldarpan629
      @musicaldarpan629 3 года назад

      Hahahahahahhahahahahahahahahahahhahahaha 😂🤣🤣🤣😂🤣

  • @megaelliott
    @megaelliott 15 лет назад

    If it was me, measure half way along each side between each corner and mark it. Then link each corner with its opposite facing mark with a pen or pencil and the point where the lines intersect is the center of the triangle.

  • @dumbidot7579
    @dumbidot7579 4 года назад

    How does one move their center of mass

  • @vovaparkourukraine1
    @vovaparkourukraine1 11 лет назад

    4:10 geographic center again. That's a heavy ruler btw

  • @vanskis7618
    @vanskis7618 7 лет назад +3

    Styrofoam is Lighter than Lead

  • @sidgtagamer
    @sidgtagamer 12 лет назад

    'thousands' of great videos

  • @megaelliott
    @megaelliott 15 лет назад

    I am sure anyone would after creating hundreds of great videos.

  • @DazHuang72
    @DazHuang72 2 года назад

    Super entertaining, must watch comedy education

  • @jackflash8756
    @jackflash8756 8 месяцев назад

    You made a slight error with the eccentric force on the bar because it causes translation as well as rotation, not just rotation.

  • @Wrobelkrzysztof1
    @Wrobelkrzysztof1 11 лет назад

    Thank you

  • @adamaqmal
    @adamaqmal 12 лет назад

    great,,,

  • @adwoatumtum
    @adwoatumtum 4 года назад +2

    *can someone please explain further why a center of mass below the bar is beneficial? Because from the drawing, I’m assuming that if the center of mass is below the bar as the athlete is right over the bar, gravity would push the athletes body further into the bar to hit it which defeats the purpose?*

    • @emilyncolon8815
      @emilyncolon8815 2 года назад

      I have the same question.

    • @idrisShiningTimes
      @idrisShiningTimes Год назад +1

      Doing this involves lesser change in mechanical energy (work done against gravity is less), hence lesser magnitude of force is required to jump over the bar. This saves the athlete's muscular energy and enables them to use the remaining energy for later jumps and not get tired

  • @thepurplebooks
    @thepurplebooks 11 лет назад

    Orange Styrofoam.. Excellent band-name!

  • @jeriiahangelo9740
    @jeriiahangelo9740 7 лет назад +1

    Wow a 10 KG ruler...This is something else

  • @anthonyrajabala
    @anthonyrajabala 14 лет назад +1

    Hi Sal Your Videos are excellent and amazing . God bless you.I think from F=Ma, 1 Kilogram * 9.8 m/s^2 (gravity) = 9.8 Newtons of force...so 1 kilo exerts 9.8 Newtons of force on earth. 1 Newton is approximately equal to 100 grams on earth.

    • @glitchy_star_classes6276
      @glitchy_star_classes6276 2 года назад

      now, heres an amazing fact to continue your reply.. the average weight of  apple is nearly as same as that weight.. so basically 1N is the weight exerted by an average ..

  • @barisaxshorty
    @barisaxshorty 11 лет назад

    so if i was in space and i arched my back and my center of mass was below me, and someone pushed me from the front i would rotate backwards around the center of mass that is below me???

  • @DeathByLight
    @DeathByLight 16 лет назад

    Great explanation!

  • @serene9532
    @serene9532 6 лет назад

    That horse😂😂😂😂 damn

  • @nightmare4eVerr1
    @nightmare4eVerr1 14 лет назад

    awome sal! your way way way way way way bettttttterr than our lame teachers!!! i owe you my good result all thanks to you! :)

  • @eieilovethis
    @eieilovethis 4 года назад

    This video was uploaded when I was 5. Wow

  • @skruvbrallor
    @skruvbrallor 10 лет назад

    "...the object, that looks like a horse..."
    Hahaha, no it doesn't!
    Thanks for your great vids!

  • @GG-uj5ru
    @GG-uj5ru 3 года назад +2

    The quality here is disturbing. Then I saw it was released on 2008

  • @q_q123
    @q_q123 4 года назад

    That's one heavy ruler

  • @bernardodocruzeiro2496
    @bernardodocruzeiro2496 5 лет назад +1

    what if there is no way a force is applied to an object center of mass because its center of mass is outside the object? does that mean that there is no way for that object to be accelerated in the force's direction, leaving as the only option the rotation of the object anywhere the force is applied?

    • @arvindcreations2465
      @arvindcreations2465 7 месяцев назад

      i mean this is pretty late, but technically, there is a way, in fact it is must for the centre of mass to be accelerated in the force's difrection even if the COM is outside the body, lets say a ring, COM is in the centre, but still uppon application of force the acceleration is still produced in the same direction

  • @Madpolis7
    @Madpolis7 12 лет назад

    @batmanownsyourass The forces of friction interfere with it.

  • @The__Creeper
    @The__Creeper 12 лет назад

    "When an object is free it rotates around its center of mass" what do you mean when you say "free?" When you put a pencil on the table and flick it it does not rotate about the center of mass unless there is a fixed point at the center of mass.

  • @dbmasters
    @dbmasters 13 лет назад

    @BR3AK1NGbenjamin It's not their own English; it's just a variation of British English which means they are not spelling "centre" incorrectly as you originally claimed.

  • @ahmedvaskar5270
    @ahmedvaskar5270 11 лет назад

    thanx

  • @gdogvibes1
    @gdogvibes1 10 лет назад +49

    A 10 kilogram ruler?? That's 22 lbs lol!

    • @ThePerfect1077
      @ThePerfect1077 7 лет назад +53

      It's 10 kilograms lets leave it at that

    • @rockstar-yp3jn
      @rockstar-yp3jn 5 лет назад

      Lol lol mat Kar lol tera jaat.lol se tu paida hua hai lol tera baap.tu indian hai na re halkat.

  • @unspaghettible
    @unspaghettible 9 лет назад +19

    +1 for horses

  • @megaelliott
    @megaelliott 13 лет назад

    @cCaglarOne I know! He has come so far!

  • @BewitchinGinger
    @BewitchinGinger 12 лет назад

    Hmm.... I'd say hippo with a toupee. Still super helpful though. :)

  • @tristan2668
    @tristan2668 10 лет назад

    Is center of mass the same as center of gravity?

  • @abhishekbhattacharjee4639
    @abhishekbhattacharjee4639 6 лет назад

    Spit fact:
    The high jump thing is called a fosberry flop