How do I find R1 current in this case with superposition theorem?

[Sughyaliope]

 

[KlausST]

Hi,

My solution:
(First, just to clarify: "Is", is not just a current, there also needs to be a voltage across "Is")
Vs is 13V, now R2 and R4 create a 6.5V source with a source resistance of 12.5 Ohms.
Combine this with R1 and you get a 6.5V source with 62.5 Ohms.

So we als know: I_R1 + I_R3 = 2A
Let's use Vx as the voltage at the bottom node (where R1, R3 and Is meet) wrt minus if the battery.
Then:
I_R3 = (13V - Vx) / 15 Ohms .... and
I_R1 = (6.5V - Vx) / 62.5 Ohms
This solves to Vx = - 1930/155 = -12.452V
And I_R1 = 0.3032A

Not 100% sure if my calculation is right.
What about a try with a simulation tool?

Klaus

 

[FvM]

Superposition theorem requires to calculate the effects of voltage and current source separately and add them. 0.3032 A is correct.