Use the symbols $N$, $\Delta N$, $T$ and $\Delta T$ to give an expression for the average activity of the sample over the interval $\Delta T$.
Use the symbols $N$, $\Delta N$, $T$ and $\Delta T$ to give an expression for the probability that a nucleus decays in the time $\Delta T$.
Use the symbols $N$, $\Delta N$, $T$ and $\Delta T$ to give an expression for the decay constant $\lambda$ for the isotope.
The isotope polonium-208 ($^{208}_{84}\text{Po}$) is radioactive and decays to form lead-204 ($^{204}_{82}\text{Pb}$). The nuclear equation for this decay is $^{208}_{84}\text{Po} \rightarrow ^{204}_{82}\text{Pb} + ^{4}_{2}\text{He}$. Determine, for the decay of one nucleus of polonium-208, the change, in $\text{u}$, of the mass.
Determine the total energy, in $\text{pJ}$, released when one nucleus of polonium-208 decays.
The polonium-208 nucleus starts at rest. The initial kinetic energy of the $^{4}_{2}\text{He}$ nucleus ($\alpha$-particle) is found to be less than the energy calculated in (i) part 2. Suggest two possible reasons for this difference.