Half-life period of a radioactive element X is same as the mean-life t...
T1/2=0.693/wavelength
tavg=1/wavelength
if both equal then
0.693/wavelength of x=1/wavelength of y
so since activity directly proportional to wavelength y has more activity
more activity implies earlier it decays sp y decays faster
Half-life period of a radioactive element X is same as the mean-life t...
Introduction:
In radioactive decay, the half-life period refers to the time it takes for half of the radioactive substance to decay. On the other hand, the mean-life time represents the average time it takes for one radioactive atom to decay. In this scenario, we are given that the half-life period of element X is the same as the mean-life time of element Y. We need to determine which element decays faster.
Understanding the concept:
To understand which element decays faster, we need to compare their decay rates. The decay rate can be defined as the number of atoms that decay per unit of time. A higher decay rate indicates a faster decay process.
Explanation:
Let's assume that both element X and element Y initially have the same number of atoms. Now, let's compare their decay rates.
Decay rate of element X:
Since the half-life period of element X is the same as the mean-life time of element Y, we can conclude that the decay rate of element X is equal to 1 atom per half-life period.
Decay rate of element Y:
The mean-life time of element Y represents the average time it takes for one radioactive atom to decay. Therefore, the decay rate of element Y is equal to 1 atom per mean-life time.
Comparison:
Since the half-life period of element X is the same as the mean-life time of element Y, their decay rates can be compared directly:
Decay rate of X = 1 atom per half-life period
Decay rate of Y = 1 atom per mean-life time
Since the half-life period is generally shorter than the mean-life time, we can conclude that the decay rate of element X is faster than the decay rate of element Y. Therefore, option (a) is incorrect.
Correct option:
The correct option is (b) - Y decays faster than X.
Justification:
Since the decay rate of element X is faster than the decay rate of element Y, element X will decay at a faster rate. Therefore, option (b) is the correct answer.
Summary:
In summary, when the half-life period of element X is the same as the mean-life time of element Y, element X decays faster than element Y. This is because the decay rate of element X is greater than the decay rate of element Y.