Finding out the mass of an object given only height

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To find the speed of a roller coaster descending from 110m to 10m without friction, apply the conservation of energy principle. The gravitational potential energy at the starting height (Eg = mgh) converts to kinetic energy as it descends. By expressing the equations symbolically, the mass cancels out, allowing for a solution that reveals the speed independent of mass. The key is to set the initial potential energy equal to the kinetic energy at the lower height. This approach leads to a surprising result that does not require knowing the mass of the object.
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Homework Statement


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


Homework Equations


Eg = mgh
v = sqrt(2Ek/m)


The Attempt at a Solution


Honestly I'm not sure where to begin when given no mass.
 
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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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