Đáp án:
\(\begin{array}{l}
1.\\
a.R = 125\Omega \\
b.I = 0,5A\\
2.\\
a.R = 7,5\Omega \\
b.\\
{I_3} = 1A\\
{I_2} = 0,5A\\
{I_3} = 0,5A
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
1.\\
a.\\
R = \dfrac{U}{I} = \dfrac{{15}}{{0,12}} = 125\Omega \\
b.\\
I = \dfrac{{{P_{dm}}}}{{{U_{dm}}}} = \dfrac{6}{{12}} = 0,5A\\
2.\\
a.\\
{R_{12}} = \dfrac{{{R_1}{R_2}}}{{{R_1} + {R_2}}} = \dfrac{{10.10}}{{10 + 10}} = 5\Omega \\
R = {R_{12}} + {R_3} = 5 + 2,5 = 7,5\Omega \\
b.\\
{I_3} = I = \dfrac{U}{R} = \dfrac{{7,5}}{{7,5}} = 1A\\
{U_2} = {U_1} = {U_{12}} = I{R_{12}} = 1.5 = 5V\\
{I_2} = \dfrac{{{U_2}}}{{{R_2}}} = \dfrac{5}{{10}} = 0,5A\\
{I_3} = I - {I_2} = 1 - 0,5 = 0,5A
\end{array}\)