# PhysicsLinear Applications: Electrical Networks

#### PullandTwist

##### Member
So I am having difficulty with the following problem;

Determine the currents in the various branches.

So I went ahead and assigned I names to the various branches and drew in flow directions to help me visualize the problem better.

From there I created the following three equations;

I1=I2+I3
2I1+3I2=10
2I1+4I3=10

Which I then put in a matrix and was able to reduce for the following solutions;

I1=35/13
I2=20/13
I3=15/13

The problem is that the book states that I should be getting;

I1=5/7
I2=20/7
I3=15/7

Where am I going wrong in setting up my equations? I know I'm not messing up going to RREF form cause my calculator is giving me the same answer. I figure I must be screwing up the initial equations.

#### Klaas van Aarsen

##### MHB Seeker
Staff member
Hi PullandTwist,

I believe your equations and solution are fine.
The stated book solution is wrong.
It looks as if it belongs to a similar problem with different resistors.
For instance with resistors $2\ \Omega, 2\ \Omega, 6\ \Omega$ and voltage $10\ \textrm{V}$.