(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

So, I need a little help with a few problems

So, say a 2kg pine cone drops from a tree 41 meters high. If it hits the ground at 10m/s then how much was lost to entropy?

Or

A 1800kg roller coaster begins at the top of 190m hill, at what height will the velocity be 24m/s and what will be its kinetic energy when it reaches a height of 10m above the ground.?

Thanks for any or all help.

2. Relevant equations

Energy of work = Force times distance

Gravitational potential = mgy

Kinetic Energy = .5 time mass time velocity squared

3. The attempt at a solution

For the 2nd one, I used mgy= .5 time mass time velocity squared but submitted 24 for the velocity to find y but I don't think it's right.

For the 1st, I used mgy+.5 time mass time velocity squared to find the energy but don't know where to go from there.

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# Homework Help: Energy needed/energy lost

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