- #1

UselessLadder

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## Homework Statement

Hi, I have a quick question about applying the RC time constant formula for a lab report. In the lab, we charged a capacitor to 20 V and then let them discharge, recording the voltage every 10 seconds, up to 240 sec. Now I was asked to graph the time vs. voltage in excel, fit an exponential trendline and obtain an equation.

## Homework Equations

The equation I got from my line is: y = 19.89e

^{-0.02x}

My lab manual gives the time constant formula as V = V

_{0}e

^{-1/t}, with t being the time constant.

I have to use the experimentally obtained equation to calculate the time constant.

## The Attempt at a Solution

I see the V

_{0}is very close to 20, so that makes sense, but I don't understand how to combine the two equations to get the time constant. It seems that V should be the final voltage, but I have 24 values, all of which would give a different x. I'm confused how to proceed from here.