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    I need help with this question.

    So for part A i thought you do Force x Distance. So did 0.04 x 8000 to get 320J

    Part b: Equation to use is 1/2mv^2 - 1/2mu^2
    1/20.025 (v^2-200^2)=320
    Rearrage to get V^2
    Then Solve- however I get 40root41. Which is 256 approx...

    Any help?
    Thanks
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    (Original post by Xphoenix)
    I need help with this question.

    So for part A i thought you do Force x Distance. So did 0.04 x 8000 to get 320J

    Part b: Equation to use is 1/2mv^2 - 1/2mu^2
    1/20.025 (v^2-200^2)=320
    Rearrage to get V^2
    Then Solve- however I get 40root41. Which is 256 approx...

    Any help?
    Thanks
    You have your equation in part b the wrong way round.
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    (Original post by zetamcfc)
    You have your equation in part b the wrong way round.
    Can you explain what you mean? tried swapping V and U around and it still doesn't come out with the right answer
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    (Original post by Xphoenix)
    Can you explain what you mean? tried swapping V and U around and it still doesn't come out with the right answer
    It should do.

    \ \frac{1}{2} 0.025 (200^2 - v^2)=320

    Solve for v.
 
 
 
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