I have a exam tommorrow so i will greatly appreciate anyone who helps me on this one. The question has to be solved using law of conservation of energy.(adsbygoogle = window.adsbygoogle || []).push({});

Q: A roller coaster starts from rest at point A and weighs 1000kg with the ppl in it and goes through the designed track. The height of the track changes 5 times. There is a pic but i dont know how to post it.

Point A:9.5m

Point B:6.5m

Point C:9.2m

Point D:0.50m

Point E:5.5m

a)What is its maximum speed?

b)With what speed does the roller coaster arrive at point E?

c)What constant braking would have to be applied at point E to stop the roller coaster within 5m.?

Analysis:

I finished part B. That was easy mgh=mgh+0.5mv^2 and the speed came out to be 8.8m/s

I have no idea how to do a and c. Before i begin. i just wanna know, the more the energy the more the accelaration right. So at the heighst point of the track the roller coaster would have the max velocity. If this is right, then i know how to do part a as well. Use point A and point C to find the max veloctiy and point C.

Part c relates to the force of friction. I could use F=ma but i dont have the time so i am stuck here.

Hope you guys understand what i am saying.

Thanks

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# Homework Help: Law of conservation of Energy question.

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