Two radioactive sources A and B initially contain equal number of radi...
Explanation:
To understand the ratio of activity of source A to source B, we need to first understand the concept of half-life.
Half-Life:
The half-life of a radioactive substance is the time it takes for half of the radioactive atoms in a sample to decay. It is a characteristic property of each radioactive material.
Source A:
Source A has a half-life of 1 hour. This means that after every hour, the number of radioactive atoms in source A will reduce by half.
Source B:
Source B has a half-life of 2 hours. This means that after every 2 hours, the number of radioactive atoms in source B will reduce by half.
At the end of 2 hours:
Let's assume that both sources A and B initially contain 'x' number of radioactive atoms.
After 1 hour, source A will have 'x/2' radioactive atoms remaining.
After 2 hours, source A will have 'x/4' radioactive atoms remaining.
After 2 hours, source B will have 'x/2' radioactive atoms remaining.
Ratio of activity:
The activity of a radioactive source is directly proportional to the number of radioactive atoms present. Therefore, we can compare the ratio of the remaining radioactive atoms in source A to that in source B.
At the end of 2 hours:
Activity of source A = 'x/4'
Activity of source B = 'x/2'
To find the ratio, we divide the activity of source A by the activity of source B:
('x/4') / ('x/2') = 1/2
Therefore, the ratio of activity of source A to that of source B is 1 : 2.
Answer:
The correct answer is option a) 1 : 2.