Công thức tính chu kỳ bán rã

Ta có chu kỳ bán rã:

     \(N=N_0e^{-\lambda t} \Rightarrow T=\dfrac{t .ln2}{ln \dfrac{N_0}{N}}\)

    \(\Delta m=m_0(1-e^{-\lambda t}) \Rightarrow T=- \dfrac{t.ln2}{ln \left ( 1-\dfrac{\Delta m}{m_0}\right )}\)

    \(\Delta N=N_0(1-e^{-\lambda t}) \Rightarrow T=- \dfrac{t.ln2}{ln \left ( 1-\dfrac{\Delta N}{N_0}\right )}\)

   \(\left\{\begin{matrix}N_1=N_0e^{-\lambda t_1}\\ N_2=N_0e^{-\lambda t_2}\end{matrix}\right. \Rightarrow T=\dfrac{(t_1-t_2)ln2}{ln \dfrac{N_1}{N_2}}\)