Question

The half-life of radium is $1600$ years. After how much time $\frac{1}{16}$th part of radium will remain undisintegrated in a sample?

Answer 1

$t_{1/2}=1600$ year

$A=\frac{1}{16}$

$A_o=1$

$t=\frac{2.303\times t1/2}{0.693}\times log16$

$t=64$ year