Two conductors with resistances of 4 ohms and 8 ohms are connected in series. The current in the circuit is 1 A.

Two conductors with resistances of 4 ohms and 8 ohms are connected in series. The current in the circuit is 1 A. Determine the resistance of the circuit, the voltage on each conductor and the total voltage of the entire section of the circuit.

R1 = 4 ohms.
R2 = 8 ohms.
I = 1 A.
U -?
U1 -?
U2 -?
R -?
For a series connection of conductors, the following formulas are valid: I = I1 = I2, R = R1 + R2, U = U1 + U2.
R = 4 ohms + 8 ohms = 12 ohms.
Let’s write Ohm’s law for the first resistance: I1 = U1 / R1.
U1 = I1 * R1,
U1 = 1 A * 4 Ohm = 4 V.
Let’s write Ohm’s law for the second resistance: I2 = U2 / R2.
U2 = I2 * R2,
U2 = 1 A * 8 Ohm = 8 V.
U = 4V + 8V = 12V.
Answer: R = 12 ohms, U1 = 4 V, U2 = 8 V, U = 12 V.