Need help simplifying equation to find the laplace transform of it

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Homework Help Overview

The discussion revolves around simplifying equations related to an electrical circuit with two loops, focusing on finding the Laplace transform of the system's response. The original poster presents two equations involving current, resistance, and capacitance, aiming to derive a single equation for analysis.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss differentiating the equations to eliminate integrals and explore the possibility of taking the Laplace transform directly. There are inquiries about the correctness of the differential equation setup and the relationship between input and output voltage across a resistor.

Discussion Status

The discussion is ongoing, with participants sharing various approaches, including differentiation and verification of the initial equations. Some express uncertainty about the next steps, while others suggest methods to simplify the problem further.

Contextual Notes

Participants note challenges in deriving a single equation from the two provided and express concerns about the setup of the differential equations. There is an emphasis on finding a relationship between the output voltage across R2 and the input.

formulajoe
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there are two loops in an electrical circuit. I've got two equations and two unknowns.
here are the equations

v(t) = I1*R1 + 1/c*int(I1*dt) - 1/c*int(I2*dt) - first loop
0 = LdI2/dt + R2*I2 - 1/c*int(I1*dt) + 1/c*int(I2*dt) - second loop

the capacitor is in the branch between the two loops.

Im drawing a blank on this. I need to simplify into one equation so I can find the laplace transform of the one equation.
the goal is to find the step response of the system using matlab.
 
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You'll want to differentiate both equations first, to get rid of those god awful integrals.

I need to simplify into one equation so I can find the laplace transform of the one equation.

There's nothing wrong with taking the Laplace transform first and then simplifying.
 
can i get a confirmation that i set up those differential equations properly? I am having some trouble with this still. if i differentiate, than i get derivative of the input. I am trying to find the output voltage which is across the R2 resistor.
 
im still having trouble with this problem. I've tried multiple methods including differentiation and solving for a variable and plugging it into the first equation but I am still where i started the other day. I am trying to find an equation that relates the output voltage across R2 to the input. I am confident my beginning equations are correct, but i don't know where to go from there.
 

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