How Do You Solve a Basic KVL Circuit Problem?

In summary, the conversation is about setting up equations for two loops, specifically the KVL equation for the left loop and the right loop, as well as the KCL equation for a junction. The person asking for help is struggling and frustrated, but eventually figures it out and realizes that it is an intense algebra problem. The final answer is Ic = (RbE1 + RaE2) / RaRb + RaRc + RbRc.
  • #1
nchin
172
0
http://imageshack.us/a/img585/9687/kvlf.jpg

the work i did on that sheet is completely wrong.

I know that Ic = Ia + Ib

but can someone help me set up the equations for the two loops please! I can't seem to figure it out and its frustrating me!

the answer is supposed to be Ic = (RbE1 + RaE2) / RaRb + RaRc + RbRc
 
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  • #2
nchin said:
http://imageshack.us/a/img585/9687/kvlf.jpg

the work i did on that sheet is completely wrong.

I know that Ic = Ia + Ib

but can someone help me set up the equations for the two loops please! I can't seem to figure it out and its frustrating me!

the answer is supposed to be Ic = (RbE1 + RaE2) / RaRb + RaRc + RbRc
attachment.php?attachmentid=57492&stc=1&d=1365133690.jpg


Write the KVL equation for the "left loop".

Write the KVL equation for the "right loop".

Write the KCL equation for either junction.
 

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  • #3
thanks i just figured it out. this is just an intense algebra problem!
 
  • #4
nchin said:
thanks i just figured it out. this is just an intense algebra problem!
Yes. Algebra is involved.
 
  • #5


I would be happy to assist with your KVL circuit problem. It seems like you are on the right track by using the equation Ic = Ia + Ib. To set up the equations for the two loops, you can start by labeling the currents flowing through each resistor and then applying KVL to each loop.

For the first loop, starting at the top left corner and moving clockwise, we have:
-IRa - IRc + E1 = 0

For the second loop, starting at the top right corner and moving clockwise, we have:
-IRb - IRc + E2 = 0

From these two equations, we can solve for IRc by substituting in the equation Ic = Ia + Ib. This will give us:
-IRc + (Ic - Ib) + E1 = 0
-IRc + Ic - Ib + E1 = 0
Ic = Ib + IRc - E1

Next, we can substitute this expression for Ic into the second loop equation to solve for IRb:
-IRb - IRc + E2 = 0
-IRb - (Ib + IRc - E1) + E2 = 0
-IRb - Ib - IRc + E1 + E2 = 0
IRb = Ib + IRc - E1 - E2

Finally, we can substitute both expressions for IRc and IRb into the equation Ic = Ia + Ib to get the final answer:
Ic = Ib + (Ib + IRc - E1 - E2) - E1
Ic = 2Ib + IRc - 2E1 - E2

Using the equation Ic = Ia + Ib, we can also solve for IRa:
IRa = Ic - Ib
IRa = (2Ib + IRc - 2E1 - E2) - Ib
IRa = Ib + IRc - 2E1 - E2

Finally, we can substitute these expressions into the original equation Ic = (RbE1 + RaE2) / (RaRb + RaRc + RbRc) to get:
Ic = (RbE1 + RaE2) / (RaRb + RaRc + RbRc)
Ic = (Rb(I
 

Related to How Do You Solve a Basic KVL Circuit Problem?

1. What is a KVL circuit?

A KVL (Kirchhoff's Voltage Law) circuit is a basic electrical circuit that follows the principle of conservation of energy. It states that the sum of all voltages in a closed loop must equal zero.

2. How do I solve a simple KVL circuit problem?

To solve a simple KVL circuit problem, you will need to apply Kirchhoff's Voltage Law and use Ohm's Law to calculate the unknown voltages and currents. You will also need to identify the direction of current flow and assign voltage polarities.

3. What are the key components of a KVL circuit?

A KVL circuit typically consists of a power source (such as a battery), resistors, and wires connecting the components. It may also include switches, capacitors, and inductors in more complex circuits.

4. How does KVL apply to real-life circuits?

KVL is a fundamental law of electricity and applies to all types of circuits, including real-life circuits found in electronic devices and power systems. It is used by engineers and scientists to analyze and design electrical circuits.

5. What are some common mistakes made when solving KVL circuit problems?

Some common mistakes when solving KVL circuit problems include forgetting to account for the direction of current flow, incorrectly applying Kirchhoff's Voltage Law, and not considering the voltage drop across components. It is important to double-check your work and make sure all the calculations are accurate.

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