Đáp án:
20km
Giải thích các bước giải:
Câu 6:
Ta có:
\(\egin{array}{l}
{P_{hp}} = \frac{{{P^2}}}{{{U^2}}}.R\\
\Rightarrow U = \sqrt {\frac{{{P^2}.R}}{{{P_{hp}}}}} = \sqrt {\frac{{{{({{10.10}^3})}^2}.4}}{{0,{{1.10}^3}}}} = 2000V
\end{array}\)
Câu 7:
\(\begin{array}{l}
{P_{hp}} = \frac{{{P^2}}}{{{U^2}}}.R\\
\Rightarrow R = \frac{{{P_{hp}}.{U^2}}}{{{P^2}}} = \frac{{{{160.10}^3}.{{({{15.10}^3})}^2}}}{{{{({{3.10}^6})}^2}}} = 4\Omega \\
\Rightarrow L = \frac{4}{{0,2}} = 20km
\end{array}\)
