Question

A radioactive nucleus decays by two different process The half life of the first process is 5 minutes and that of the second process is $30 s$. The effective half-life of the nucleus is calculated to be $\frac{\alpha}{11}$ s The value of $\alpha$ is _______

Answer 1

The correct answer is 300.
dtdN1​​=−λ1​N
dtdN2​​=−λ2​N
dtdN​=−(λ1​+λ2​)N
⇒λeq​=λ1​+λ2​
⇒t1/2​1​=3001​+301​=30011​
⇒t1/2​=11300​