Answer to Question #212614 in Physics for UTTAM KUMAR

Question

The half- life period of a radioacve isotope is 30 days. If we start with 10 g of the substance, then the amount le aer 90 days is:

Answer 1

The radioactive decay law says

$$m(t)=m_0 2^{-t/t_{1/2}}=(10\:\rm g)*2^{-90/30}=1.25\: g$$