Five identical resistors with a resistance of 10 ohms each are connected to an electrical circuit through which

Five identical resistors with a resistance of 10 ohms each are connected to an electrical circuit through which a current I = 6A flows. What is the voltage on an ideal voltmeter?

Five identical resistors, with a resistance of R = 10 Ohm each, are connected in an electrical circuit, so that the total resistance of the circuit R total can be calculated by the formula: R total = R + 1 / (1 / (2 ∙ R) + 1 / (2 ∙ R)), then R total = 2 ∙ R; R total = 2 ∙ 10 = 20 (Ohm). From the condition of the problem it is known that a current I = 6 A flows through the circuit, then from Ohm’s law I = U / R it follows that U total = I total ∙ R total or U total = 6 ∙ 20 = 120 (V), and U total: 2 = 2 ∙ U. Then an ideal voltmeter (an ideal voltmeter if no current flows through it, that is, Iv = 0 A) on the first resistor will show the voltage: U = U total: 4; U = 120: 4 = 30 (V).
Answer: An ideal voltmeter shows a voltage of 30 V.