What is the half-life period of a radioactive material if its activity drops to of its initial value of 30 years?
- (A)9.5 years
- (B)8.5 years
- (C)7.5 years✓ Correct
- (D)10.5 years
Answer: (C)
Solution
Activity follows . Given at years. Taking natural log: . Since , we have , giving years.
JEE Main · 2022 · 27 Jul 2022 · Shift 1 · Single correct option