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After 300 days, the activity of a radioa...

After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps is

A

20000

B

10000

C

7000

D

25000

Text Solution

Verified by Experts

The correct Answer is:
A
As, activity droped from 5000 dps to 2500 dps in 150 days means `T_(1//2)=150"days"`
`implies300"days"=2T_(1//2)`
So, initial activity `2xx5000xx2=20000` dps
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