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1. I have a exponential growth curve for a potential difference vs time graph. Is it possible to calculate the time constant from the gradient of the curve at time 0 seconds?
2. (Original post by Jas1947)
I have a exponential growth curve for a potential difference vs time graph. Is it possible to calculate the time constant from the gradient of the curve at time 0 seconds?
The easiest way to measure the time constant from an exponential graph where the capacitor is charging would be to first calculate , then use the graph to see which time corresponds to this value of P.D

If it were discharging you would use a similar method but using 1/e instead
3. (Original post by Jas1947)
I have a exponential growth curve for a potential difference vs time graph. Is it possible to calculate the time constant from the gradient of the curve at time 0 seconds?
Yup. Just draw a tangent to the curve at t=0; also draw a line representing the asymptote of the steady-state value. The crossing point of the two on the x-axis represents the time constant.

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Updated: January 23, 2017
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