Practicing Mesh Analysis I came across this problem and te answer is really alluding me and I believe is just one polarity that I'm not understanding, the problem is the following...
Vs=10V, R1=100Ω, R2=50Ω, R3=25Ω, Is=2A.
Calculate the current I1 in amps that goes through R3 from left to right. Enter >only the numerical answer for I1 in the text box, omit the units. Note: this >problem can be done different ways, but try using Mesh Analysis.
Now, I'm setting up my equation using the passive sign convention as following.
Vs voltage rise R2 voltage drop R3 voltage rise (since current is flowing clockwise entering the "negative" terminal of R3)
so it would look something like this:
-Vs+R2(I1-I2)-R3(I1)=0
-10+50(I1-(-2))-25(I1)=0
Now the answer to the question is 1.2 which I could achieve if the voltage across R3 was in fact " 25(I1) " instead of negative as in my equation, the thing is that I don't understand what I'm doing wrong and I don't Understand why it is positive if it is a voltage rise?
+R2(I1..
then you must also use+R3I1
as I1 goes in the same direction through R2 as it goes through R3. \$\endgroup\$In
in mesh loop all theIn * R
on that loop must have the same sign. \$\endgroup\$