Atoms And Nuclei Question 365

Question: A 280 days old radioactive substance shows an activity of 6000 dps, 140 days later its activity becomes 3000 dps. What was its initial activity?

Options:

A) 20000 dps

B) 24000 dps

C) 12000 dps

D) 6000 dps

Show Answer

Answer:

Correct Answer: B

Solution:

  • λ=2.303280logA06000=2.303420logA03000 On solving, we get, A0=24000dps.


NCERT Chapter Video Solution

Dual Pane