First slide

Radio activity

Question

After 280 days, the activity of a radioactive sample is 6000 dps. The activity reduces to 3000 dps after another 140 days. The initial activityof the sample in dps is

Moderate

A

6000
B

9000
C

3000
D

24000

Solution

Here the activity of the radioactive sample reduces to half in 140 days. Therefore, the half-life of the sample is 140 days. 280 days is its two half -lives. So before two half-lives its activity was $(2^{2} x present activity)$
$∴ Initial activity = 2^{2} x 6000 = 24000 dps .$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App