Motion in a Straight Line: Crash Course Physics #1

  • Published on Mar 31, 2016
  • In this, THE FIRST EPISODE of Crash Course Physics, your host Dr. Shini Somara introduces us to the ideas of motion in a straight line. She talks about displacement, acceleration, time, velocity, and the definition of acceleration. Also, how does a physicist discuss speed as opposed to a police officer? And did you deserve that ticket? You can figure it all out with the help of Physics!
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Comments • 4 374

  • Stephanie Edwards
    Stephanie Edwards 22 hours ago +1

    When is physics going to die????

  • Tui Ngatai
    Tui Ngatai 3 days ago


  • Howie 367
    Howie 367 4 days ago +1

    I’m here to cram for my exam in the next 24 hours

  • BKB
    BKB 5 days ago

    Now I now :0

  • Coaching in Dyslexia & Workplace Skills

    WTF is displacement anyway

  • Coaching in Dyslexia & Workplace Skills

    The Displacement Curve gets about 3 seconds of explanation. Not very helpful.

  • Coaching in Dyslexia & Workplace Skills

    Easier to understand at .75 normal speed.

  • Coaching in Dyslexia & Workplace Skills

    This presenter goes so fast that even though I knew this stuff she makes my brain melt. Slow down. PLEASE.

    KIKIM_THE_GAMER 8 days ago

    very helpful

  • Kai S.
    Kai S. 9 days ago

    Put on subtitles and slow down the speed of the video to 0.5. Thank me later.

  • MJ Lizarda
    MJ Lizarda 10 days ago

    How do I learn this when I’m in 7th grade

  • Renzo Ojastro
    Renzo Ojastro 12 days ago

    Im 11 and i kinda understand a little bit

  • Speroking
    Speroking 16 days ago

    Her voice is (almost) as fast as hanks


  • Speroking
    Speroking 16 days ago +1

    Ok, ok I got this!

    You lost me at “so you want to learn physics?”

  • Ababy U.
    Ababy U. 17 days ago

    My brain: reduce the playback speed... Me: ok , 0.75. Reads comment, woman talking brain, she's still fast. Me: 0.50 🙄 now even the music is slow motion. This is ridiculous. I'm dropping Physics class ...we can/t keep up with the jibber jabber..

  • Elias Lawson
    Elias Lawson 20 days ago

    This is great at 1.5 speed

  • Unknown 4.0
    Unknown 4.0 22 days ago

    Bruh y is she talkin like eminem

  • anbuselvi ponnusamy
    anbuselvi ponnusamy 23 days ago

    in my school we learned that velocity is the direction and speed

    SLIM SHADY 26 days ago

    Fk all i heard was like"mterss mters blah blah x t"

  • M F
    M F Month ago

    امتحان فزكس باجر 😒😒💔 !

  • Andrew Olive Tree Mixing

    I cant follow this thought exercise because of the 100km per hour limit in North Dakota USA

  • Luke Hall
    Luke Hall Month ago

    This woman is heavenly

  • Ella M
    Ella M Month ago +1

    is anyone else rly confused by how she got the answer to the equation at 9:37 ?? I'm so lost lmao

  • Foxyte
    Foxyte Month ago

    1:44 big foot under the trees...👀

  • Brian Ellis
    Brian Ellis Month ago +1

    Isn't the "average velocity" in the definition of acceleration equation actually final velocity, not the average? Delta v is Vfinal minus Vinitial, not Vaverage minus Vinitial. Can we get... an updated video? That's bound to confuse my students.
    The entire section about average velocity seemed out of place. The measurement is fine for some situations, but in a study of kinematics it becomes problematic if it's just thrown out there.

  • sidra sanger
    sidra sanger Month ago

    This only confused me more.

  • ArtisticMuffin Wolf

    Me an American when she said kilometers: wtf?

  • housta ghani
    housta ghani Month ago

    what what wha wha wha all i hear is mate mate good day

  • Ali RJ
    Ali RJ Month ago

    This video has great information but I feel like pouring information, and no time to digest = overwhelming over velocity

  • Matthew GOODCHILD
    Matthew GOODCHILD Month ago

    You clearly got A's in exams lol

  • John Campbell
    John Campbell Month ago +23

    her: introduces math equation in science
    me: mouth dropping in horror

    • Andy Jiang
      Andy Jiang 20 hours ago

      ofc math is so important in physics... Higher lvl needs advanced calculus and linear algebra etc.

  • Danny Ellis
    Danny Ellis Month ago

    I don't get why you flash equations up there for half a second and show her face almost constantly. I think I'd get more out of it with a lot less face time and maybe somebody doing actual calculations on screen.

  • maja trtanj
    maja trtanj Month ago

    i don't get it

  • Ra Coon
    Ra Coon Month ago

    Quick tip guys, slow down the video. It sounds a little distorted, but after a minute you don't even notice it. It's easier to keep up and relate to what she is saying. A lot of people speed up when teaching cause there so much information and so little time to say it. The beauty of this is you can slow down their time to your liking

  • 米莉
    米莉 Month ago +9

    -Gets pulled over by the cops-
    -pulls out notepad,calculator and Jimmy Neutron science-
    -argues with the cops with said science for about 15 minutes only to realize I was wrong-
    Next time I’ll just take the ticket thx 😓

  • thatTUESDAYchannel
    thatTUESDAYchannel Month ago

    Doesnt the v in v = v0 + at mean velocity at time t not average velocity?

  • thatTUESDAYchannel
    thatTUESDAYchannel Month ago


  • oyunadawa lokiyisangkim

    you are a better teacher than my professors. i feel i get all the goodsides upsides no downsides. glad this is free. better than university classes.

  • Ada
    Ada Month ago

    thank you Dr. Shini Somara!

  • _.lxibx._
    _.lxibx._ Month ago

    My brain hurts

  • Mateo Oliva
    Mateo Oliva Month ago +1

    oh and The vid helped a lot btw thankssss!!

  • Mateo Oliva
    Mateo Oliva Month ago +3

    7:27 pretty sure that's like a stomach growl in the background

  • Twisted Sno
    Twisted Sno Month ago

    Thank you!!

  • John Jacob Jingleheimer Schmidt

    Video goes way too fast for anyone that actually wants to learn physics. If you already have a good understanding then I'm sure it's fine. I'd rather have a 25 minute video that actually explains the science instead of a rushed 10 minute video.

  • Sugar And spice
    Sugar And spice Month ago +291

    Her: "I hear you want to learn physics."
    Me, being a pessimist: "No I want to pass my test tomorrow and nothing my teacher taught me makes sense."

    • Michael Hedrick
      Michael Hedrick 4 days ago

      Option 3 chemistry physics biology health/PE

    • loay alalawi
      loay alalawi Month ago +2

      Sugar And spice ikr i just wanna pass my test tmr that iknow nothing about

    • Cyntia Puga
      Cyntia Puga Month ago +1


    • Messing Around
      Messing Around Month ago +2

      I literally have a test tomorrow, Sooo relatable

    • Option 3
      Option 3 Month ago +3

      Physics is pretty much the only interesting topic imo tho

  • Potato __
    Potato __ Month ago +1

    You're talking so fast that I can't compose everything

  • TheProgrammingJedi
    TheProgrammingJedi Month ago


  • Comrade Emu
    Comrade Emu Month ago

    you would still get a ticket

  • Jane Adams
    Jane Adams Month ago

    Slow down your speed of talking. If you do this, you will be more effective.

  • Tantibus Draws
    Tantibus Draws 2 months ago

    First episode, and I'm already lost.

  • kevindanielpg
    kevindanielpg 2 months ago

    Damn, as not native english Speaker, slow down, like a hell of a lot down, damn I had to pause and rewind like 13 times

  • 2019
    2019 2 months ago +1

    Is this on a GCSE or A Level Physics Course?

  • stannny Okike
    stannny Okike 2 months ago

    i cant keep up....i cant even take notes

  • Bean
    Bean 2 months ago

    She sounds identical to Hermione. (Emma Watson)

  • nicole escobar
    nicole escobar 2 months ago

    I saw your physics videos for my exam and I got 100% in physics. Thanks ❤

  • Obaid Paracha
    Obaid Paracha 2 months ago

    Why is this messing with my head ?
    7:28 | Average velocity = initial velocity + acceleration * time
    shouldn't it be | final velocity = initial velocity + acceleration * time ?
    shouldn't average velocity be | Average velocity = initial velocity + (acceleration * time ) / 2

  • Marc Co
    Marc Co 2 months ago

    how did she get the acceleration at 9:40?

  • 蔡德灿
    蔡德灿 2 months ago +1

    What is armor penetrating phisics?

  • Gin Tonic
    Gin Tonic 2 months ago

    9:39 How is a=5 m/s²? When I convert the formula to a I get 244/7 m/s²

    • Adi Borochov
      Adi Borochov 2 months ago

      It's 244/49. You put t instead of t^2 that is supposed be in the formula.

  • Yura Tea
    Yura Tea 2 months ago

    To know what is your average acceleration you just need to multiply the distance by 2 and divide it by the time squared. For example you went 100 meters in 5 sec. It means that your acceleration is 200/25= 8m/s2
    Let's say I went 100 meters in 5 sec and now I'm going about an hour. I'm going this long distance and I'm not sure if there's an acceleration? My speedometer is broken. What if I'm going evenly? I'm not sure about it. What to do in this case?