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Math Help - Help with this D.E please

  1. #1
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    Help with this D.E please

    1/v dv=-ke^(s/h) ds

    Where k is a constant

    Im trying to get v as a function of s by sep. of variables and am fairly confused by the algebra. Any help would be appreciated.
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  2. #2
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    Quote Originally Posted by msu_15 View Post
    1/v dv=-ke^(s/h) ds

    Where k is a constant

    Im trying to get v as a function of s by sep. of variables and am fairly confused by the algebra. Any help would be appreciated.
    What is h?

    If it is just another constant then your equation is ready to be integrated...

     \int \frac{1}{v} dv = -k \int e^{\frac{s}{h}}ds
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  3. #3
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    Quote Originally Posted by msu_15 View Post
    1/v dv=-ke^(s/h) ds

    Where k is a constant

    Im trying to get v as a function of s by sep. of variables and am fairly confused by the algebra. Any help would be appreciated.
    The variables are already separated in this case. My solution only works if k and h are constants too.

    Integrating : \int \frac{dv}{v} = \int -ke^{(s/h)} ds

    ln|v| =  -ke^{\frac{s}{h}} \times \frac{h}{s} + C

    Can you solve it from there? I tried going further but could only get to s^s =f(v)
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  4. #4
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    h is a constant as well. my bad
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