# Finding out the mass of an object given only height

#### DPXJube

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.

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#### rock.freak667

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 )

#### Borek

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

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