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Capacitors - Graph of lnV over t Watch

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    Can someone explain to me why the gradient of lnV over t is 1/RC?

    Ive tried rearranging the formula Vt = V0e^-t/RC but i end up with lnVt/V0 = -t/RC
    but i dont know what to do from there?
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    (Original post by LotusTK)
    Can someone explain to me why the gradient of lnV over t is 1/RC?

    Ive tried rearranging the formula Vt = V0e^-t/RC but i end up with lnVt/V0 = -t/RC
    but i dont know what to do from there?
    Have you studied log laws? \log \frac{A}{B} = \log A - \log B.
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    (Original post by morgan8002)
    Have you studied log laws? \log \frac{A}{B} = \log A - \log B.
    Oops. Ohh yes.

    I think ive got it now. The formula we have is

    lnVt = t x -1/RC + lnV0

    where lnV0 is the y intercept.

    This seems to match up to what im seeing on the graph.

    Thanks, cant believe i didnt see the log rule in there.
 
 
 
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