Đáp án:
Δh' = 25cm
Giải thích các bước giải:
Chúng sẽ cân bằng ở vị trí:
$\begin{array}{l}
\dfrac{{10.{m_1}}}{{{S_1}}} + 10.\Delta h.{D_n} = \dfrac{{10.{m_2}}}{{{S_2}}}\\
\Leftrightarrow \dfrac{1}{{{S_1}}} + 1000.0,1 = \dfrac{2}{{{S_2}}}\\
\Leftrightarrow \dfrac{2}{{{S_2}}} - \dfrac{1}{{{S_1}}} = 100\left( 1 \right)\\
\dfrac{{10.({m_1} + m)}}{{{S_1}}} = \dfrac{{10.{m_2}}}{{{S_2}}}\\
\Leftrightarrow \dfrac{{1 + 2}}{{{S_1}}} = \dfrac{2}{{{S_2}}}\\
\Leftrightarrow \dfrac{2}{{{S_2}}} - \dfrac{3}{{{s_1}}} = 0\left( 2 \right)\\
\left( 1 \right) - \left( 2 \right) \Rightarrow \dfrac{3}{{{S_1}}} - \dfrac{1}{{{S_1}}} = 100\\
\Leftrightarrow \dfrac{2}{{{S_1}}} = 100 \Rightarrow {S_1} = \dfrac{2}{{100}} = \dfrac{1}{{50}}{m^2}\\
\Rightarrow {S_2} = \dfrac{1}{{75}}{m^2}\\
\dfrac{{10.{m_1}}}{{{S_1}}} + 10.\Delta h'.{D_n} = \dfrac{{10.({m_2} + m)}}{{{S_2}}}\\
\Leftrightarrow \dfrac{1}{{\dfrac{1}{{50}}}} + \Delta h'.1000 = \dfrac{{2 + 2}}{{\dfrac{1}{{75}}}}\\
\Leftrightarrow \Delta h\prime = 0,25m = 25cm
\end{array}$