An object with mass m moving on x'x and Ep(x) = (1/2)*k*(x^2 - 4)^2

AI Thread Summary
The discussion revolves around the potential energy function Ep(x) = (1/2)*k*(x^2 - 4)^2 for a mass m moving along the x-axis. Participants confirm that calculations are mostly correct but emphasize the need to determine feasible solutions for when velocity v=0. They inquire about the total energy required for the system to reach x=0 and the corresponding velocity at that energy level, specifically when total energy is 9/2 k. Additionally, there is a critique regarding the scale of a sketch presented, prompting clarification on the proximity of specific x positions. Overall, the focus is on refining calculations and understanding the energy dynamics of the system.
Michael_0039
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Homework Statement
An object with m mass moving on x'x and Ep(x) = (1/2)*k*(x^2 - 4)^2 . x is the position of the object and k>0 (constant)

The object starts with zero velocity from x0=1

1) V(max) = ? and X @ V(max)
2) Which is the position speed will be zero again ?
Relevant Equations
nil
Hi !

This is my try:

New Doc 2019-11-17 23.40.59_1.jpg


New Doc 2019-11-17 23.40.59_2.jpg
Is that correct ?

Thanks
 
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Almost correct. All of your calculations are right, but you need to figure out which solutions for ##v=0## can actually happen. How much total energy would be required for the system to achieve ##x=0##? What would be the velocity at that point if the total energy is ##\frac 9 2 k##?
 
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In addition to @tnich's observation, I have a minor comment. Your sketch is a little out of scale. Which two of the x positions 1, 2, √7 should be closest together?
 
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