A radioisotope has a half life of 10 days. If tofay there is `125 g ` of it left, what was its mass 40 days earlier ?A. `600g`B. `1000g`C. `1250g`D. `2000g`

A radioisotope has a half life of 10 days. If tofay there is `125 g `

1.	A radioisotope has a half life of 10 days. If tofay there is `125 g ` of it left, what was its mass 40 days earlier ?A. `600g`B. `1000g`C. `1250g`D. `2000g`
Answer» Correct Answer - D `T=nxxt_(1//2)` `:. n=(40)/(10)=4` `N=((1)/(2))^(n)N_(0)` `:. N_(0)=125xx(2)^(4)=125xx16=2000`

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A radioisotope has a half life of 10 days. If tofay there is `125 g ` of it left, what was its mass 40 days earlier ?A. `600g`B. `1000g`C. `1250g`D. `2000g`

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