Question

If the amount of a radioactive substance is increased three times, the number of atoms disintegrating per unit time would:

• A. be double
• B. not be change
• C. be triple
• D. be $\frac{1}{3}$rd of the original number of atoms

Answer 1

The correct option is C be triple

$\frac{dN}{dt}=-\lambda N$

If N becomes three times then the number of atoms disintegrating per unit time also becomes three times.

Hence, option C is correct.