(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

In my lab we where given a simple circuit and told to get some data of a capacitor charging and discharging. Thus I now have a graph of current vs time, we used semi-log paper for this so the graph would be a straight line.

We are given the value of the resistor and capacitor from the professor.

We are now asked to find the RC time constant of both charge the discharge, then find the C of our capacitor from our data and compare it with the given value from our professor.

Knowns:

R=(0.94x10^6)ohms

C=(62x10^-6) farads

I=(11x10^-6) amps

Our lab asked us to turn up the voltage until we got 11uA therefore I can use ohms law to find my voltage using V=IR

V=(11x10^-6)*(0.94x10^6) = 10.34V

2. Relevant equations

V=IR

Q=CV

T=RC

3. The attempt at a solution

I know one value of C simply because my professor gave it to me.

Given C = (62x10^-6) farads

Now I must use the data I recorded to calculate C. This is where I'm stuck, I have a current vs time graph but cannot see how to get a C value with it and can't find the RC time constant of my data.

Tjvelcro

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: RC time constant lab, Current vs time

**Physics Forums | Science Articles, Homework Help, Discussion**