Question on linearizing equation

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SUMMARY

The discussion focuses on linearizing the equation derived from Kirchoff's Voltage Law for an RC circuit, specifically addressing the charging and discharging of a capacitor. The equation in question is Voltage(t) = VoltageMax * (1 - e^(-t / RC)). The user initially attempted to simplify this to linearize the data but faced challenges in determining the maximum voltage and correctly applying logarithmic properties. Ultimately, it was clarified that the user needed to focus on the discharging capacitor equation instead of the charging equation.

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  • Understanding of Kirchoff's Voltage Law
  • Familiarity with RC circuit theory
  • Knowledge of natural logarithms and their properties
  • Ability to manipulate exponential equations
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  • Learn about the equations governing discharging capacitors
  • Explore the application of natural logarithms in circuit analysis
  • Review common mistakes in circuit analysis and how to avoid them
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Homework Statement


toconvert.jpg


I posted the entire question, but I am only conserned with part B.

There was a circuit drawing on there but it is irrelevant for this part of the problem. One can solve it without knowing the circuit drawing.

Homework Equations



The application for Kirchoff's Voltage Law results in the equation

Voltage(time in secs) = VoltageMax * (1 - e^(-t / RC) )

The circuit in question is an RC circuit where I have a single capacitor and resistor in a loop.

The Attempt at a Solution


[/B]
I have been struggling over how to figure out how to linearize the data. I have simplified the equation to the following form:

[voltageAtTimeT / maxvoltage = (1 - e^(-t /RC) )

And then I wanted to take the natural log to take the -t/RC out of the exponent and linearize it.

However, I run into two problems: I do not know how to find the MaxVoltage as of now and the right hand side would become ln[ 1 - e^(-t / RC) ]. I can not simplify this right-hand side further as there is no law of logarithms that says that ln( a + b) can be simplified into a simpler form.

Thus, I am stuck, and I would appreciated any guidance in how to solve this problem.
Thanks in advance.
 
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If you wait forever, what do you think the maximum voltage across the charging capacitor will be?
What if you did some algebra to isolate the exponential on one side of the equation and then take the natural log?

Actually, your measurements were on the discharging capacitor, so you need to linearize that equation. The equation you quoted is for the charging capacitor.
 
Thank you very much for the help!

It is sad that I made such a careless error in choosing the wrong equation.
 
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