Em tham khảo nha :
\(\begin{array}{l}
{m_P} = 1,6726 \times {10^{ - 27}}kg\\
{m_e} = 9,1094 \times {10^{ - 31}}kg\\
{m_n} = 1,6748 \times {10^{ - 27}}kg\\
\dfrac{{{m_e}}}{{{m_p}}} = \dfrac{{9,1094 \times {{10}^{ - 31}}}}{{1,6726 \times {{10}^{ - 27}}}} = 5,45 \times {10^{ - 4}}\\
\dfrac{{{m_e}}}{{{m_n}}} = \dfrac{{9,1094 \times {{10}^{ - 31}}}}{{1,6748 \times {{10}^{ - 27}}}} = 5,44 \times {10^{ - 4}}\\
\dfrac{{{m_p}}}{{{m_n}}} = \dfrac{{1,6726 \times {{10}^{ - 27}}}}{{1,6748 \times {{10}^{ - 27}}}} \approx 1
\end{array}\)
