Conservation of Energy Questions

AI Thread Summary
The discussion revolves around applying the conservation of energy principle to solve physics problems involving kinetic and potential energy. In the first question, the kinetic energy of a 0.5 kg ball is used to determine its maximum height when tossed upward, ignoring air resistance. The second question involves a 265.3 kg roller coaster car starting from a height of 114.9 meters, where its speed at ground level is calculated using energy conservation. Additionally, the work done by friction in stopping the car and the distance it travels before coming to rest are also analyzed. The thread highlights the challenges some users face in understanding these concepts and seeks assistance with relevant equations.
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Question #1


A ball of mass 0.5 kg is tossed upward into the air. When it leaves your hand, it has a kinetic energy of 138 Joules. Use conservation of energy to find how high it goes. (Ignore air resistance)





Question #2


A roller coaster car with a mass of 265.3 kg starts from a height of 114.9 meters above the ground just before rolling down the frictionless track. Using conservation of energy, find the speed of the car just as it reaches the ground.


After the car reaches the ground, it travels horizontally on the track, where a frictional force of 999.6 Newtons slows the car to a stop. What is the work done on the car in bringing it to rest?


How far will the car go before it comes to rest?



I don't have a clue what I am doing, I SUCK at physics! Thanks for the help!
 
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Well, you probably have some equations you're familiar with?
 

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Thread 'Variable mass system : water sprayed into a moving container'

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