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The number of U^(238) nuclei in a rock s...

The number of `U^(238)` nuclei in a rock sample equal to the number of `Pb^(206)` atoms. The half life of `U^(238)` is `4.5xx10^(9)` years. The age of the rock is

A

`4.5xx10^(9)y`

B

`9xx10^(9) y`

C

`13.5xx10^(9)y`

D

`18xx10^(9)y`

Text Solution

Verified by Experts

The correct Answer is:
A
Given `N=(N_(o))/(2) , :. (N)/(N_(0))=(1)/(2)`
that means `t=1` half life
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