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Homework Help: Urgent help needed on car project

  1. Sep 5, 2005 #1
    I got an assignment in physics that is really hard for me, and I am having a lot of trouble even getting an idea. I am supposed to build a car that starts under its own power. I am allowed to have some sort of trigger device. If anyone has done this in the past or they know of links that could help me it would be greatly appreciated.
    1. No prefabricated wheels
    2. No electrical/commercially available motors
    3. Must be made from everday materials (no kit)
    4. Must have two axles.
    5. The propulsion mechanism must be internal (no slingshots or ramps)
    6. No compressed gas, or explosive/flammable devices
    7. If water is used, it must be contained and cannot spill on the floor.
    Performance (30 points max)
    10 points if it moves one car length (+ 1 point for additional 2 car lengths)
    Fastest car: 1st=10 points 2nd=9 points, etc...
    Greatest distance "
    Lightest car "
    Originality/theme/durability= ( 30 points max)
  2. jcsd
  3. Sep 5, 2005 #2
    You could use a mouse trap for the propulsion mechanism.

  4. Sep 5, 2005 #3
    Maybe you could try attaching some balloons to it. Fill the balloons with air and let the air out quickly, this would accelerate the car as long as it was light.
    If you want to go with this, let me know and Ill try and find you a link to some pics of these cars, they did this for 3rd yr design in my dept.
  5. Sep 5, 2005 #4
    Any links would be appreciated. So if there is a good car design that involves balloons that would definately help me out.
  6. Sep 5, 2005 #5


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    I say use torsion power. Kinda like how those toys work whwere you put the car down and pull it backwards and you hear it crank up. Then you put it down and it drives off :D.
  7. Sep 5, 2005 #6
    How would you go about building a torsion powered car?
  8. Sep 5, 2005 #7


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    Gold Member

    :confused: :confused: :confused: :confused:

    I know how to make a catapult using torsion, thats it lol
  9. Sep 5, 2005 #8
    Build the infamous mouse trap car. If you want to add some power, carefully remove one end of the metal bar that is stapled to the wood. Give the coiled spring on the trap an extra twist. fasten it back with an extra staple.

    Nails make good axles. plastic buttons make good bushings for the nails. Tuna cans are good for wheels.

    There is a good design here, but I encourage you to come up with your own, and have some fun with it.

    http://www.andrew.cmu.edu/user/tpaulk/webpage.htm [Broken]

    Rubberbands used in various configurations also work well.
    Last edited by a moderator: May 2, 2017
  10. Sep 6, 2005 #9
    Sorry, I just checked the website and it looks like photos were removed.

    But try and think how you could attach balloons to a car made out of balsa wood or something. You could have several balloons that force air out of one small nozzle maybe?
  11. Sep 6, 2005 #10
    Wouldn't ballons come fall under # 5, " no compressed gas"?
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