Question

What percentage of original radioactive substance is left after 5 half-life time.

पर्याय

• 20%

• 3%

• 5%

• 10%

Answer 1

3%

Explanation:

${\displaystyle \frac{N}{No}={\left(\frac{1}{2}\right)}^n={\left(\frac{1}{2}\right)}^5=\frac{1}{32}}$ = 3%