Radioactive half-life — UPSC Physics Optional IFoS 2024 Paper II

A sample contains 4\text{ mg} of {}^{210}\text{Bi}. If the half-life of radioactive {}^{210}\text{Bi} is 5\text{ days} and the average energy of the \beta-particles emitted is 0\cdot 34\text{ MeV}, then at what rate does the sample emit energy?