User Tag List

12 Last

Results 1 to 10 of 12

  1. #1

    Default Will these vehicles run? A puzzle from the past


  2. #2
    Oberon
    Guest

    Default

    The first one will tend to roll forward; the second one won't.

  3. #3
    Senior Member
    Join Date
    Dec 2007
    MBTI
    ISFP
    Enneagram
    9w1
    Posts
    824

    Default

    Wouldn't the second one move since there is a continuous stream of water to propel it forward? Once the lead ball left the trough, there would be no force to act on the vehicle, right? (looks like the trough is not touching the ground)

    Science > SolitaryPenguin, so I am just guessing.

    *edit*

    I take that back, the water isn't hitting the ground. I am stumped then.


    /wanders off to eat cake
    Last edited by SolitaryPenguin; 12-23-2008 at 10:31 AM. Reason: Because I am American

  4. #4
    Senior Member Misty_Mountain_Rose's Avatar
    Join Date
    Jul 2008
    MBTI
    INTJ
    Enneagram
    4w5
    Posts
    1,123

    Default

    Quote Originally Posted by oberon View Post
    The first one will tend to roll forward; the second one won't.
    +1

    Edit - Assuming the vehicles are on flat surfaces.
    Embrace the possibilities.

  5. #5
    にゃん runvardh's Avatar
    Join Date
    Jun 2007
    MBTI
    INFP
    Enneagram
    6w7 sx/so
    Socionics
    IEI
    Posts
    8,559

    Default

    I'm inclined to agree with Oberon on this one. Part of the gravitational energy pulling the lead balls down will transfer into forward motion due to the 45 in #1. #2 on the other hand, though the water is coming out of the hose, the force created is being negated when the water hits the reclaimer.
    Dreams are best served manifest and tangible.

    INFP, 6w7, IEI

    I accept no responsibility, what so ever, for the fact that I exist; I do, however, accept full responsibility for what I do while I exist.

    [SIGPIC][/SIGPIC]

  6. #6
    Senior Member Grayscale's Avatar
    Join Date
    Dec 2007
    MBTI
    istp
    Posts
    1,962

    Default

    the 'equal and opposite reaction' that would propel the first vehicle is the movement of the lead balls out the back... the water-based vehicle does not have any gross kinetic output because it is a "closed loop"

  7. #7
    Banned
    Join Date
    Jul 2008
    MBTI
    type
    Posts
    9,100

    Default

    The second method could be akin to thrust vectoring, if only more pressure were used, and the water were shooting backwards after hitting the ramp. As built though, I don't think it's going anywhere.

  8. #8
    Emperor/Dictator kyuuei's Avatar
    Join Date
    Aug 2008
    MBTI
    enfp
    Enneagram
    8
    Posts
    13,877

    Default

    Am I a bit retarded for thinking that the first one's balls would just roll down that ramp onto the ground?? I don't see how it makes the car move.
    Kantgirl: Just say "I'm feminine and I'll punch anyone who says otherwise!"
    Halla74: Think your way through the world. Feel your way through life.

    Cimarron: maybe Prpl will be your girl-bud
    prplchknz: i don't like it

    In Search Of... ... Kiwi Sketch Art ... Dream Journal ... Kyuuei's Cook book ... Kyu's Tiny House Blog ... Minimalist Challenge ... Kyu's Savings Challenge

  9. #9
    Feline Member kelric's Avatar
    Join Date
    Sep 2007
    MBTI
    INtP
    Posts
    2,169

    Default

    Quote Originally Posted by kyuuei View Post
    Am I a bit retarded for thinking that the first one's balls would just roll down that ramp onto the ground?? I don't see how it makes the car move.
    Well, when the ball hits the 45 degree ramp, falling down, the ramp will cause the ball's direction to change (from straight down, as gravity pulls it, to partially horizontal), forcing the ball to move away from the back of the truck. Since the momentum of the overall system (balls + truck) must stay the same (ignoring friction losses, etc.), the truck will move forward as the released ball moves back. But it won't move much (assuming the mass of each ball is pretty small compared to that of the truck + balls still in the hopper). Assuming you're the person who has to pick up the balls and reload them into the hopper, you'd be better off just throwing them all away and pushing the truck by hand.

    Oh no... I sound like my old physics teacher...
    [SIGPIC][/SIGPIC]

  10. #10
    Senior Member me_plus_one's Avatar
    Join Date
    Sep 2008
    MBTI
    ESTP
    Posts
    194

    Default

    Haha... I am pretty sure that none of them will actually move more than a few centimetres.

    The first one might tned to move forwards, as kelric said, because the momentum has to stay the same, but I think the vehicle is way to heavy to actually move.

    The second one...well, I don't think it will move. I mean, the water is getting back from where it has left and besides, it's not even directed horizontally.

Similar Threads

  1. [MBTItm] INFx's - favorite TV shows from the past?
    By INTPness in forum The NF Idyllic (ENFP, INFP, ENFJ, INFJ)
    Replies: 33
    Last Post: 01-10-2010, 07:58 PM
  2. [MBTItm] INTx's - favorite TV shows from the past?
    By INTPness in forum The NT Rationale (ENTP, INTP, ENTJ, INTJ)
    Replies: 7
    Last Post: 12-31-2009, 09:52 AM
  3. Natalie from the Dixie Chicks
    By Usehername in forum Popular Culture and Type
    Replies: 2
    Last Post: 10-18-2007, 07:18 AM
  4. From the slums of Shoalin, its the GZA!
    By GZA in forum Welcomes and Introductions
    Replies: 8
    Last Post: 08-14-2007, 10:51 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Single Sign On provided by vBSSO