The two conductors are connected in series. The current in the circuit is 3A, voltage is 30V.

| March 11, 2021 | education

The two conductors are connected in series. The current in the circuit is 3A, voltage is 30V. Find the resistance of the second conductor if the resistance of the first is 5 ohms.

I = 3 A.

U = 30 V.

R1 = 5 ohms.

R2 -?

With a series connection of conductors, the total resistance of the circuit is R the sum of the connected resistances R1 and R2: R = R1 + R2 and the current strength in all conductors is the same I = I1 = I2.

R2 = R – R1.

We express the total resistance of the circuit R from Ohm’s law for the section of the circuit: R = U / I, where U is the total voltage in the circuit, I is the current in the circuit.

We find the resistance of the second conductor by the formula: R2 = U / I – R1.

R2 = 30 V / 3A – 5 Ohm = 10 Ohm – 5 Ohm = 5 Ohm.

Answer: the second conductor has a resistance R2 = 5 ohms.



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