Đáp án:

${{U}_{hp2}}=2{{U}_{hp1}}$

Giải thích các bước giải:

$\begin{align}
  & {{S}_{1}}=1c{{m}^{2}};{{U}_{1}}=200000V \\ 
 & {{S}_{2}}=2c{{m}^{2}};{{U}_{2}}=100000V \\ 
\end{align}$

điện trở 2 dây:

$\begin{align}
  & \dfrac{{{R}_{1}}}{{{R}_{2}}}=\dfrac{\rho \dfrac{l}{{{S}_{1}}}}{\rho \dfrac{l}{{{S}_{2}}}}=\dfrac{{{S}_{2}}}{{{S}_{1}}}=2 \\ 
 & \Rightarrow {{R}_{1}}=2{{R}_{2}}(1) \\ 
\end{align}$

Công suất hao phí:

$\begin{align}
  & \dfrac{{{P}_{hp1}}}{{{P}_{hp2}}}=\dfrac{{{R}_{1}}\frac{{{P}^{2}}}{U_{1}^{2}}}{{{R}_{2}}.\dfrac{{{P}^{2}}}{U_{2}^{2}}}=\dfrac{{{R}_{1}}}{{{R}_{2}}}.\dfrac{U_{2}^{2}}{U_{1}^{2}} \\ 
 & =\dfrac{2{{R}_{2}}}{{{R}_{2}}}.\dfrac{{{100000}^{2}}}{{{200000}^{2}}} \\ 
 & =\dfrac{1}{2} \\ 
 & \Rightarrow {{U}_{hp2}}=2{{U}_{hp1}} \\ 
\end{align}$