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A radioactive material reduces to 1/8th ...

A radioactive material reduces to `1/8`th of its initial amount in 18000 y. Find its half-life period.

Text Solution

Verified by Experts

Here, t=18000 y and `N/N_0=1/8=1/2^3`
From equation, `N=N_0/2^(t//T)` , we get
`1/2^3=1/2^(18000//T)` or , 3T=18000 or , T=6000 y
Alternative method :
Let initial amount of radioactive substance be 1 and half-life is T.

According to question,
3T=18000 or , `T=18000/3`=6000 y
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