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A radioactive isotope has a half-life of...

A radioactive isotope has a half-life of T years. How long will it take the activity o reduce to 3.125% its original value?

Text Solution

Verified by Experts

`R/R_(0)=(1/2)^(n)`
`(3.125)/100=(1/2)^(n)`
`1/32=(1/2)^(n)=(1/2)^(5)" "[because100/3.125=32]`
`n=5,t/T=5`
t = 5T
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