Question

The decay constant $K$ of a radioactive sample is the probability of decay of an atom in unit time. Then,

• A. $ \lambda $ decreases as the atom becomes older
• B. $ \lambda $ increases as the age of atoms increases
• C. $ \lambda $ independent of the age of atoms
• D. $ \lambda $ behaviour of $ \lambda $ A with time depends on the nature of the activity

Answer 1

Answer: (C)

Decay constant of radioactive sample is reciprocal of the time after which the number of atoms of a radioactive substance decreases to $36.8\%$ of their number of present initially and it does not depend on the age of the atoms.