Ball rolling down a segment then up a parabolic segment

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A 181 g ball is released from a height of 5.19 m, rolling down a 21° incline before ascending a parabolic segment defined by y=x²/4. The conservation of energy principle is applied, where initial kinetic and potential energy equals final kinetic and potential energy. The discussion reveals confusion about the calculations, particularly regarding the energy transformations as the ball moves. Ultimately, it is clarified that the ball will rise to the same height it started from due to energy conservation, despite initial miscalculations. This realization enhances the understanding of energy conservation principles in physics.
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Homework Statement


A 181 g ball is released from rest H=5.19 m above the bottom of the track shown in Figure. It rolls down a straight 21° segment, then back up a parabolic segment whose shape is given by y=x2/4, where x and y are in m. How high will the ball go on the right before reversing direction and rolling back down?
C10P81.jpg


Homework Equations


Ki+Ui=Kf+Uf
K=mv^2/2


The Attempt at a Solution


I am not sure how to start this because everytime i go to one direction i hit a dead end.
At the beginning it has both Ki=0 and Ui=0 correct?
Then at the final it has Kf and Uf right?
 
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Here is my work but I don't even think I am on the right track...

This is for rolling down incline
Physics7.jpg



This is for rolling up the parabola
Physics8.jpg

EDIT: I put the wrong dominator in for the very last part when calculating Y it should be 4, but that anwser did not work either
 
WOOOOOOW I am so sorry for wasting everyones times the parabola made me over think this equation since Ki+Ui=Kf+Kf...energy would force the ball up the same height as it began.
 
The question gave you additional information to deceive you. Realizing this in the end only makes you understand energy conservation better. It's hardly wasting anyone's time.
 
Yeah, I see what you mean but I didn't need to make a thread after.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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