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Homework Help: Motion Question

  1. Mar 26, 2010 #1
    Nice, easy fun really.

    1. The problem statement, all variables and given/known data

    There is a frictionless rollercoaster, at a height of 99m. The mass of the car is 2000kg, weight is 19 613N. The initial velocity of the car suspended at the top is 0, it is then dropped down a sheer (90 degrees) vertical drop for 49m.

    GPE is ~1 960 000J

    I need to calculate the acceleration of the car after it has dropped, and the time it takes to complete the 49m drop, as well as the final speed it is travelling. Kinetic energy couldn't hurt either :p

    attachment.php?attachmentid=24679&stc=1&d=1269664269.png

    2. Relevant equations
    5 equations of motion.


    3. The attempt at a solution
    Meh, I've just rearranged a formula to find acceleration, but i don't have time or final velocity to work off.

    Cheers guys, no clue where to start.
     

    Attached Files:

  2. jcsd
  3. Mar 26, 2010 #2

    rl.bhat

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    Homework Helper

    Use law of conservation of energy.
    Since roller coaster is frictionless, car is falling freely.
     
  4. Mar 27, 2010 #3
    Cheers mate, I've done the calculations all seems to work out fine.

    However, under freefall, you just feel 1G right, not weightlessness?
     
  5. Mar 27, 2010 #4

    rl.bhat

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    Homework Helper

    Yes. 1 g.
     
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