Đáp án: $U=2000\,\,\,\left( V \right)$
Giải thích:
Công thức: ${{P}_{hp}}=\dfrac{{{P}^{2}}}{{{U}^{2}}}.R$
Tóm tắt:
$\begin{cases}P=10.10^3\,\,\,\left(W\right)\\R=4\,\,\,\left(\Omega\right)\\P_{hp}=0,1.10^3\,\,\,\left(W\right)\end{cases}$
$\,\,\,\,\,\,\,{{P}_{hp}}=\dfrac{{{P}^{2}}}{{{U}^{2}}}.R$
$\Rightarrow 0,1\,.\,{{10}^{3}}=\dfrac{{{\left( {{10.10}^{3}} \right)}^{2}}}{{{U}^{2}}}.4$
$\Rightarrow {{U}^{2}}=\dfrac{{{\left( {{10.10}^{3}} \right)}^{2}}}{0,1\,.\,{{10}^{3}}}.4$
$\Rightarrow {{U}^{2}}=4000000$
$\Rightarrow U=2000\,\,\,\left( V \right)$