Find velocity from Force graph using Work Theorem and Energy

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The discussion revolves around using the work theorem and energy principles to find velocity from a force graph. The user initially struggled with incorrect calculations due to misreading the graph but later corrected the error and successfully calculated the final velocity at 3 meters. Suggestions were made to utilize LaTeX for clearer presentation of equations, which the user found beneficial for future use. The conversation highlights the importance of accurate data representation in solving physics problems. Overall, the interaction emphasizes learning from mistakes and improving problem-solving techniques.
Max
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Homework Statement

:[/B]

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Homework Equations

W= \integral(Fxdx) W = \delta KE

The Attempt at a Solution


I used the definition of work to find the final velocity at 2m, and then work theorem together with integration for the changing force. I ended up having different solutions at first but then attempted to find acceleration instead for the constant force, and then plugged into find time it took it to reach 2m.
Then I used that data to find final velocity at 3m. It turned out very well. I just didn't understand why my first solution was wrong,
 

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Max said:
Then I used that data to find final velocity at 3m. It turned out very well. I just didn't understand why my first solution was wrong,
If you show us exactly what you did and how you calculated your first solution, we should be able to help you.
 
I found out the error! I copied the graph wrongly so when I plugged in for integration, it was off! Jesus! Thanks though. Next time, I will post my handwritten note!
 
Max said:
Next time, I will post my handwritten note!
Better yet, familiarize yourself with LaTeX and use it instead of handwritten notes.

BTW, (belatedly) welcome to PF.
 
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kuruman said:
Better yet, familiarize yourself with LaTeX and use it instead of handwritten notes.

BTW, (belatedly) welcome to PF.
I downloaded Latex as you suggested but not sure how it works. It was an over 1Gb download
 
Max said:
I downloaded Latex as you suggested but not sure how it works. It was an over 1Gb download
Sorry, you misunderstood me. You didn't have to download LaTeX, although it will come in handy for work that is not PF related. You can embed LaTeX equations directly into the PF pages and there is a nifty quick guide to get you started. Just click LaTeX near the bottom of the page, all the way to the left from UPLOAD and to the right of the question mark. This will get you started. The LaTeX you downloaded, save for later use. It's great for writing papers, reports and anything that requires a lot of equations.
 
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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