Final answer:
To find the current i in the given circuit, we can use symmetry and Ohm's law. By setting up and solving equations using Kirchhoff's laws, we can find the values of I₁, I₂, and I₃, which can then be used to calculate the total current i.
Step-by-step explanation:
In this circuit, the current i can be found using symmetry and Ohm's law. Since e1 = e2 = e = 7V and r1 = r2 = r = 3.6Ω, we can simplify the circuit by making a symmetric equivalent circuit.
Using Kirchhoff's laws, we can write the following equations:
E₁ - I₁R₁ - I₂R₂ = 0
-E₂ + I₁R₁ - I₃R₃ = 0
By solving these equations, we can find the values of I₁, I₂, and I₃.
Once we have the values of I₁, I₂, and I₃, we can calculate the total current i = I₁ + I₂ + I₃.