Задача 31587.

Schoolboy gathered scheme depicted in the first figure. After its connection to the ideal DC voltage source turned out that the ammeter shows a current of 0.9 A and a voltmeter - voltage of 20 V. When the student switched one of the conductors of the voltmeter from point 1 to point 2 (. See the second figure), voltmeter began to show strain 19, and an ammeter - current 1 A. how many times greater than the resistance impedance voltmeter ammeter?

Detailed solution with a short recording conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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