Build a Roller Coaster: Tips for 2 Loops & 2 Hills

AI Thread Summary
The physics class project involves building a roller coaster for a golf ball using recycled materials, with specific requirements for two loops and two hills. The first hill and loop are functioning, but the second hill presents challenges as it needs to achieve a minimum height of 20 cm after starting at ground level. Attempts to elevate the second hill using boxes and sharper inclines have been unsuccessful. The project also requires the final loop to be positioned at the end, with the ball needing to stop near an egg without causing damage. Suggestions for improving the second hill's design and materials are sought to meet these criteria.
Chem4Life
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So my physics class (No, it's not homework, per se, so I didn't put it in that section) decided we were going to build roller coasters. (Basically, it's a big pain. I wish we hadn't.)
Anyway, here are the rules:

Has to be for a golf ball, made out of recycled materials. This also means no materials for construction (but chicken wire is allowed, and I used it for my first hill.. The second hill just didn't work..), and no prefabricated materials (Legos, Kenex, etc)
2 loops, 2 hills.
Loops: Obviously, just have to have vertical displacement. I've got those down pretty well. They work, anyway.
Hills: Have to have a minimum 20 cm displacement. This is the problem..

I've got the first hill and loop, but now that I'm on the second hill, I'm on the ground (because I started at a certain hight, and you have to go down, obviously..) and I can't make it go back up. We tried putting it on boxes, and making the incline longer and more sharp, but nothing's worked..

Any suggestions for how to make it work or better things to make the second hill out of? Boxes and Chicken Wire just aren't cutting it at this point..
 
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Chem4Life said:
So my physics class (No, it's not homework, per se, so I didn't put it in that section) decided we were going to build roller coasters. (Basically, it's a big pain. I wish we hadn't.)
Anyway, here are the rules:

Has to be for a golf ball, made out of recycled materials. This also means no materials for construction (but chicken wire is allowed, and I used it for my first hill.. The second hill just didn't work..), and no prefabricated materials (Legos, Kenex, etc)
2 loops, 2 hills.
Loops: Obviously, just have to have vertical displacement. I've got those down pretty well. They work, anyway.
Hills: Have to have a minimum 20 cm displacement. This is the problem..

I've got the first hill and loop, but now that I'm on the second hill, I'm on the ground (because I started at a certain hight, and you have to go down, obviously..) and I can't make it go back up. We tried putting it on boxes, and making the incline longer and more sharp, but nothing's worked..

Any suggestions for how to make it work or better things to make the second hill out of? Boxes and Chicken Wire just aren't cutting it at this point..

Welcome to the PF.

It's still schoolwork, so it belongs in the Homework Help forums. I've moved it for you.

What exactly are the rules of this project? You understand that KE and PE trade off, right? So just because you are at ground level, doesn't mean that you can't climb back up a rise trading off some of your KE for PE. You also have rotational KE in your golf ball as it rolls along...
 
Well, the hill sort of works at this point. It almost stops at the end, and when it goes back down, it speeds up well enough.. We're just altering it, because now the second loop just can't go around. We're changing loop materials, but yes, the concept is grasped, I suppose you could say. The execution is a bit.. complicated.

Oh, the worst part, besides the building is that, to get extra credit the 2nd loop has to be at the end, and the golf ball then has to roll to a stop without friction or anything cushioning or sticky, and stop within an inch of an egg. It can touch the egg, but can't crack it.
 
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