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
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
- [AIPMT 2006]
- A
$R_1=R_2$
- B
$R_1=R_2 {e^{ - \lambda \left( {t_1- t_2} \right)}}$
- C
$R_1=R_2{e^{\lambda \left( {t_1 - t_2} \right)}}$
- D
$R_1=R_2 \left( {\frac{{t_1}}{{t_2}}} \right)$
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[Given : Half-life of $U-238$ is $4.5 \times 10^9$ years; $\log _e 2=0.693$ ]
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- [IIT 2024]
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