A radioactive sample has half-life of `5` years. Probability of decay in `10` years will be.

Options

A. `50%`
B. `75%`
C. `100%`
D. `60%`

Answer

B

Explanation

Number of half lives, `n=(10)/(5)=2`
`(N)/(N_(0))=((1)/(2))..=((1)/(2))^(2)=(1)/(4)rArrN=(1)/(4)N_(0)`
Amount decayed `=N_(0)-N=N_(0)-(1)/(4)N_(0)=(3)/(4)N_(0)`
`=N_(0)-N=N_(0)-(1)/(4)N_(0)=(3)/(4)N_(0)`
Hence, the probability of decay in ten years is `75%`.