Solved: PHYSICS Question for NEET | Sushrut

Back to Directory

NEET PHYSICSEasy

For radioactive material, the half-life is 10 minutes. If initially, there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is:

A

20

B

10

C

30

D

15

Step-by-Step Solution

Identify Given Values:

Half-life ( $T_{1/2}$ ) = 10 minutes.
Initial number of nuclei ( $N_0$ ) = 600.
Number of disintegrated nuclei = 450.

Calculate Remaining Nuclei ( $N$ ):

$N = N_0 - \text{disintegrated nuclei}$ .
$N = 600 - 450 = 150$ .

Determine Decay Factor:

Ratio of remaining to initial nuclei: $\frac{N}{N_0} = \frac{150}{600} = \frac{1}{4}$ .

Relate to Half-Lives:

We know that $\frac{1}{4} = (\frac{1}{2})^2$ . This means 2 half-lives have passed ( $n=2$ ) .

Calculate Time ( $t$ ):

$t = n \times T_{1/2}$ .
$t = 2 \times 10 \text{ minutes} = 20 \text{ minutes}$ .

Practice Mode Available

Master this Topic on Sushrut

Join thousands of students and practice with AI-generated mock tests.

Solved: PHYSICS Question for NEET | Sushrut