Đáp án:
\(\begin{array}{l}
a.\\
R = 4\Omega \\
b.\\
I = 2,4A\\
c.\\
{I_1} = {I_3} = 1,2A\\
{U_{CD}} = 1,2V
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a.\\
{R_{12}} = {R_1} + {R_2} = 4 + 4 = 8\Omega \\
{R_{34}} = {R_3} + {R_4} = 3 + 5 = 8\Omega \\
R = \frac{{{R_{12}}{R_{34}}}}{{{R_{12}} + {R_{34}}}} = \frac{{8.8}}{{8 + 8}} = 4\Omega \\
b.\\
I = \frac{E}{{R + r}} = \frac{{12}}{{4 + 1}} = 2,4A\\
c.\\
{I_1}{R_{12}} = {I_3}{R_{34}}\\
8{I_1} = 8{I_3}\\
{I_1} + {I_3} = 2,4\\
{I_1} = {I_3} = 1,2A\\
{U_{CD}} = - {U_{AC}} + {U_{AD}} = - {I_1}{R_1} + {I_3}{R_3} = - 1,2.4 + 1,2.3 = 1,2V
\end{array}\)