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Four resistots

С1  4.00 Find the reading of ammeter $A_1$ given that the resistors have resistances of $1~\Omega$, $2\Omega$, $3 \Omega$, $4 \Omega$, and voltmeter $V$ shows a voltage of $10~\mathrm{V}$.

1 Parameterization is chosen: two unknown currents or one unknown potential. 0.20
2 The system of equation is written 2 × 0.30
3 Obtained that
\[I_2 = U_0 \frac{\frac{1}{R_1 R_4}-\frac{1}{R_2R_3}}{\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}+\frac{1}{R_4}}\]
0.50
4 Obtained that
\[I_1 = U_0 \frac{\left( \frac{1}{R_1} + \frac{1}{R_2} \right) \left( \frac{1}{R_3} + \frac{1}{R_4} \right)}{\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}+\frac{1}{R_4}}\]
0.50
5 Different permutations of the resistances are analyzed (at least two distinct arrangements are considered). 0.60
6 Found that
\[R_1 = 1~\Omega \leftrightarrow R_4 = 4 ~\Omega \quad R_2 = 2~\Omega \leftrightarrow R_3 = 3~\Omega\]
1.00
7 \[I_1=4.8~\mathrm{A}\] 0.30
8 \[I_1=5.0~\mathrm{A}\] 0.30