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Homework Help: Finding out the mass of an object given only height

  1. Jan 30, 2012 #1
    1. The problem statement, all variables and given/known data
    A roller coaster starts at rest from a height of 110m and accelerates down the track to a height of 10.0 m. Find the speed it can each, assuming there is no friction

    2. Relevant equations
    Eg = mgh
    v = sqrt(2Ek/m)

    3. The attempt at a solution
    Honestly I'm not sure where to begin when given no mass.
  2. jcsd
  3. Jan 30, 2012 #2


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    Homework Helper

    Hi DPXJube,

    How about we try applying the law conservation of energy here. (it might involve mass in the beginning but write it out :wink: )
  4. Jan 30, 2012 #3


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    Staff: Mentor

    Assume mass of m, solve using symbols only. Prepare for a surprise.
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