Calculating Capacitance from Voltage-Time Data

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jdog6
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This is for a lab I have done and I am stuck on this,

Question : Plot a curve of In (1 - V/Vo) vs time and calculate C from the slope of the line.

Initial equation = V = Vo(1-e^-t/RC)
Calculated Linear Equation : In (1 - V/Vo) = -t/RC
Therefore from y = mx + b = m = -t/RC (i think)
Then, C = -t/Rm

m = -72.673
R = 10 000 ohms
C = what we are looking for
-t = ? do i use any of my times

Also, C (accepted value) = 6000x10^-6 Farad
Therefore, answer should be near this.

Please help me out! I'm totally stumped. Thank you.
 
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i believe i have a lead t = time constant but i don't know what that is...
 
Yes you must plot all of your data. At each time, t, you measured some voltage, v,. Plot the points t, and

[tex]\ln ( 1 - \frac v v_0 )[/tex]

where v is your measured values. You should get something linear, find the slope of the line.