Assertion : If the half life of a radioactive substance is $40\, days$ then $25\%$ substance decay in $20\, days$
Reason : $N = {N_0}\,{\left( {\frac{1}{2}} \right)^n}$
where, $n = \frac{{{\rm{time\, elapsed}}}}{{{\rm{half \,life \,period}}}}$
Assertion : If the half life of a radioactive substance is $40\, days$ then $25\%$ substance decay in $20\, days$
Reason : $N = {N_0}\,{\left( {\frac{1}{2}} \right)^n}$
where, $n = \frac{{{\rm{time\, elapsed}}}}{{{\rm{half \,life \,period}}}}$
- [AIIMS 1998]
- A
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
- B
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
- C
If the Assertion is correct but Reason is incorrect.
- D
If the Assertion is incorrect but the Reason is correct
Similar Questions
$A$ and $B$ are two radioactive substances whose half lives are $1$ and $2$ years respectively. Initially $10\, g$ of $A$ and $1\,g$ of $B$ is taken. The time (approximate) after which they will have same quantity remaining is ........... $years$
$A$ and $B$ are two radioactive substances whose half lives are $1$ and $2$ years respectively. Initially $10\, g$ of $A$ and $1\,g$ of $B$ is taken. The time (approximate) after which they will have same quantity remaining is ........... $years$
If $T$ is the half life of a radioactive material, then the fraction that would remain after a time $\frac{T}{2}$ is
If $T$ is the half life of a radioactive material, then the fraction that would remain after a time $\frac{T}{2}$ is
During mean life of a radioactive element, the fraction that disintegrates is
During mean life of a radioactive element, the fraction that disintegrates is
Half-life of a substance is $10$ years. In what time, it becomes $\frac{1}{4}\,th$ part of the initial amount ........$years$
Half-life of a substance is $10$ years. In what time, it becomes $\frac{1}{4}\,th$ part of the initial amount ........$years$
The mean life time of a radionuclide, if its activity decrease by $4\%$ for every $1h$ , would be .......... $h$ [product is non-radioactive i.e. stable]
The mean life time of a radionuclide, if its activity decrease by $4\%$ for every $1h$ , would be .......... $h$ [product is non-radioactive i.e. stable]