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Number of nuclei of a radioactive substa...

Number of nuclei of a radioactive substance are `1000` and `900` at times `t=0` and time `t=2 s`. Then, number of nuclei at time `t=4s` will be

A

800

B

790

C

700

D

810

Text Solution

Verified by Experts

The correct Answer is:
D
Here, `N_(0)=1000, N=900" at " t= 2s`.
In `t=2s`, number of nuclei left `=90%`
In next 2 s (i.e. when total time = 4 s),
number of nuclei left `=90%`" of "900=810`
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