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    I'm really confused by this question, any help would be greatly appreciated!

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    Mark scheme

    It asks me to find the displacement after 2 seconds of travel time only knowing v and a in terms of x (as opposed to t). I don't remember ever doing this before and the exercise book doesn't seem to have a formula for it as far as I can tell.

    Thanks in advance!
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    (Original post by BobFredric)
    I'm really confused by this question, any help would be greatly appreciated!

    Paper

    Mark scheme

    It asks me to find the displacement after 2 seconds of travel time only knowing v and a in terms of x (as opposed to t). I don't remember ever doing this before and the exercise book doesn't seem to have a formula for it as far as I can tell.

    Thanks in advance!
    Replace v with dx/dt in the expression in a) so that you have an equation in x and t. You'll need to rewrite the answer to a) as a single fraction, square root and then separate the variables. The integration is still quite challenging, given that it is supposed to be just C4.
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    That's crazy! I haven't practiced C4 much but I don't remember it ever getting that hard! I couldn't get to a solution even after many attempts, but thanks for giving me the way into it .
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    (Original post by BobFredric)
    That's crazy! I haven't practiced C4 much but I don't remember it ever getting that hard! I couldn't get to a solution even after many attempts, but thanks for giving me the way into it .
    The process of replacing v with dx/dt is one you need to know, but hopefully the integration wouldn't be as hard.
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    Yes, I've got it on my notes now ^^.
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    I found it difficult too,but the whole point was v=dx/dt...that's so strange.
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    (Original post by Vesniep)
    I found it difficult too,but the whole point was v=dx/dt...that's so strange.
    Why is it strange? You have an equation connecting v and x, you need one connecting x and t.
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    (Original post by tiny hobbit)
    Why is it strange? You have an equation connecting v and x, you need one connecting x and t.
    I know it is very simple actually, but I couldn't think of it under the pressure of time.The 'strange' fact is that other students couldn't do this too,no matter how easy it was finally.The only part that was slightly difficult was the integration.
 
 
 

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