One radioactive isotope of hydrogen has a half-life of $12\text{ years}$. A sample contains $40$ million atoms of this isotope. How many atoms of this isotope remain after $24\text{ years}$?
- A$20$ million
- B$10$ million
- C$5$ million
- Dzero
Physics 5054 · O Level · Half-life
One radioactive isotope of hydrogen has a half-life of $12\text{ years}$. A sample contains $40$ million atoms of this isotope. How many atoms of this isotope remain after $24\text{ years}$?