What resistance conductor should be included in the external circuit of the generator with an emf of 220 V

What resistance conductor should be included in the external circuit of the generator with an emf of 220 V and an internal resistance of 0.1 Ohm so that the voltage at its terminals is 210 V?

Determine the voltage drop across the internal resistance of the power supply.

ΔU = E – U = 220 – 210 = 10 V.

According to Ohm’s law, we determine the current in the circuit.

I = ΔU / r = 10 / 0.1 = 100 A.

Let’s apply Ohm’s law to the complete circuit.

I = E / (R + r), where E is the EMF of the circuit, R is the external resistance of the circuit, r is the internal resistance of the power source.

(R + r) = E / I.

R = (E / I) – r = (220/100) – 0.1 = 2.2 – 0.1 = 2.1 Ohm.

Answer: The resistance of the conductor is 2.1 ohms.