At `t=0`, number of radioactive nuclei of a radioactive substance are `x` and its radioactivity is `y`. Half-life of radioactive substance is `T`. Then,

Options

A. `(x)/(y)` is constant throughout
B. `(x)/(y) gt T`
C. Value of `xy` remains half after one half-life
D. Value of `xy` becomes one fourth after one half-life

Answer

A, B, D

Explanation

`x=N` and`y= lambdaN, (x)/(y)=(1)/(lambda)=(T)/(0.693)`
`xy=lambda N^(2)`, so after one half-life it's value becomes `1//4^(th)` of its value.