In a radioactive material the activity at time `t_(1)` is `R_(1)` and at a later time `t_(2)`, it is `R_(2)`. If the decay constant of the material is `lambda`, then

Options

A. `T_(B) lt T_(A)`
B. `T_(B) = T_(A)`
C. `T_(B) gt T_(A)`
D. Either (a) or (c) depending on whether the asteroid is approaching or moving away from A

Answer

A

Explanation

`T= (T_(0))/(sqrt(1- ((v)/(c))^(2)))`
`T_(0)` is measured by the person at rest
`T rarr` Time observed by the person on earth in relative motion
`therefore T_(A) gt T_(B) (T_(B)= T_(0))`