defence exam ITBP (Telecommunication) Head Constable Mock Test 2024 Physics Nuclear Physics Radioactivity
A radioisotope has a half-life of 20 hours. After 60 hours the fraction of its isotope remains is
1
\(\dfrac{1}{8}\)
2
\(\dfrac{1}{4}\)
3
\(\dfrac{1}{3}\)
4
\(\dfrac{1}{2}\)