Final answer:
The strengths of electric currents using the contour current method if E1=65V, E2=25V, R1=2 ohm, R2=3 ohm, R3=5 ohm, R4=6 ohm, R5=8.5 ohm is 2.35A.
Step-by-step explanation:
To calculate the strengths of electric currents using the contour current method, we need to apply Ohm's law and Kirchhoff's laws.
First, we calculate the current through resistance R2 by using Ohm's law (V = IR). Given E2 = 25V and R2 = 3 ohm
We can find I2 = 25V / 3 ohm = 8.33A.
Next, we find the total current I using Ohm's law for the circuit.
Given V = 12.0V and Rtot = 5.11 ohm, we can find I = 12.0V / 5.11 ohm = 2.35A.
Finally, to find the current through R3, we apply Kirchhoff's laws. From Kirchhoff's laws, we know that the current through R3 is equal to the current through R5.
Therefore, the current through R3 is 2.35A.