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Finding out the mass of an object given only height

  • Thread starter DPXJube
  • Start date
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.


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: )


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

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