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

2. Relevant equations

Z = √(X_{C}^{2}+ X_{L}^{2})

X_{L}= 2πƒL

X_{C}= 1 / 2πƒC

I = V/Z

3. The attempt at a solution

First off, thank you for all of the help this semester. I'm sure you'll be seeing questions from me in the spring also. Here is how I'm thinking about this problem:

1. Using the above equations, I find the reactances of the inductor and capacitor to be3141.59Ωand1.59Ω, respectively.

2. Add: X_{L}+ (-X_{C}) =3140Ω = Z

Note: I used -X_{C}because on a graph the capacitor's reactance would be a downward pointing vector. However, no matter if I add or subtract these reactances the final current would be equivalent since 1.59Ω is much, much smaller than 3141.59Ω.

3. I find the current by using the equation ofV/Z; however, the issue is that I have two voltage sources-- so whichVdo I use?

I decided that I could use superposition. So first equation: I = 1.2V / 3140 =.382mA. Second equation: 0.8V / 3140 =.255mA

4. Now I superimpose them. Since the 1.2V source moves rightward and the 0.8V source moves leftward, I did the following:

→ ← →

.382 - .255 =.127mA

5. My final result seems to be off. Relative to the voltage through the 1.2V source, here is the graph:

As you can see, the difference is 56μA, or about .056mA at the voltage peak of the 1.2V source.

One thing I noticed I did wrong is that the current of .127mA would be present when at the voltage peak of a single source circuit. Since I have 2 voltage sources the way I compared my current to my voltage peak doesn't make sense.

If someone could highlight where I am going wrong I would be very appreciative. The finals are on Wednesday and I've been studying for 6hrs so I'm gonna head to bed and check on this in the AM. Thanks :)

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

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: Finals Study Time! A Two Source Circuit w/Inductor, Cap, and Resistor

Have something to add?

Draft saved
Draft deleted

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