# The circuit consists of two conductors in series, the resistance of the second conductor is 5 ohms

**The circuit consists of two conductors in series, the resistance of the second conductor is 5 ohms. The current in the circuit is 1A. The voltage at the ends of the first resistor is 10V. Determine the total voltage in the circuit and the resistance of the second resistor.**

R1 = 5 ohms.

I = 1 A.

U2 = 10 V.

R -?

R2 -?

With a series connection of conductors, the following formulas are valid:

R = R1 + R2 the total resistance of the circuit is equal to the sum of the resistances;

I = I1 = I2 the current strength is the same for all resistances in series connection;

U = U1 + U2 the total voltage is the sum of the voltages across each resistance ..

Let’s write Ohm’s law for a section of the circuit for the second resistance: I2 = U2 / R2.

R2 = U2 / I2.

R2 = 10 V / 1 A = 10 ohms.

R = R1 + R2.

R = 5 ohms + 10 ohms = 15 ohms.

Answer: R2 = 10 ohms, R = 15 ohms.