Mesh currents, emfs, and resistances

[madbo517]

Howdy!

Looking for help with the following problem (#33). I found it easiest to take a picture of the problem statement and the figure and another of my work (I am working on learning LaTeX so I can write them neatly in posts, but until then, I hope a picture is sufficient).

I got the system of 3 formulas in the picture, but in all the practice ones we did, we were given V, in this problem we're given one of the currents, but I'm not sure how to use that in this problem.

I'm using mesh currents (ia, ib, and ic), because that's how these types of problems were explained to us, although I'm sure there are multiple methods to solve this problem.

Thanks for the help!

 

[I like Serena]

Howdy!

Looking for help with the following problem (#33). I found it easiest to take a picture of the problem statement and the figure and another of my work (I am working on learning LaTeX so I can write them neatly in posts, but until then, I hope a picture is sufficient).

I got the system of 3 formulas in the picture, but in all the practice ones we did, we were given V, in this problem we're given one of the currents, but I'm not sure how to use that in this problem.

I'm using mesh currents (ia, ib, and ic), because that's how these types of problems were explained to us, although I'm sure there are multiple methods to solve this problem.

Thanks for the help!

Hi madbo517! Welcome to MHB! :)

Your set of equations looks fine.

Next, use that $i_c = i_6$.

 

[madbo517]

Hi madbo517! Welcome to MHB! :)

Your set of equations looks fine.

Next, use that $i_c = i_6$.

OH, of course!
Thank you so much!

So I used the fact that ic=i6, and started backtracking. I figured out what ib and ia were, and then finally that V = 8.3V. But the answer in the book says it is 48.3V.

What am I missing?

 

[I like Serena]

OH, of course!
Thank you so much!

So I used the fact that ic=i6, and started backtracking. I figured out what ib and ia were, and then finally that V = 8.3V. But the answer in the book says it is 48.3V.

What am I missing?

You're not missing anything.

I haven't checked your answer, but it's easy enough to verify if there is a calculation mistake.

What did you get for $i_a$ and $i_b$?
Fill them in in your equations and see if they are satisfied.

 

[madbo517]

You're not missing anything.

I haven't checked your answer, but it's easy enough to verify if there is a calculation mistake.

What did you get for $i_a$ and $i_b$?
Fill them in in your equations and see if they are satisfied.

Duh - I got it! Was a silly calculator mistake.

Thank you so much!