$$\begin{array} {|c|c|c|c|} \hline \text{name} & \text{symbol} & \text{value} & \text{unit} \\ \hline \text{fundamental charge} & e & 1.6 \times 10^{-19} & C \\ \hline \text{mass of electron} & m_e & 9.11 \times 10^{-31} & kg \\ \hline \text{mass of proton} & m_p & 1.6726 \times 10^{-27} & kg \\ \hline \text{mass of neutron} & m_n & 1.6749 \times 10^{-27} & kg \\ \hline \text{acceleration due to gravity} & g & 9.81 & ms^{-2} \\ \hline \text{Planck's constant} & h & 6.6 \times 10^{-34} & Js \\ \hline \text{speed of light in vacuum} & c & 3 \times 10^8 & ms^{-1} \\ \hline \end{array}$$