The masses of two radioactive substances are same and thier half-lives are 1 year and 2 years respectively. The ratio of their activities after six year will be:
Correct answer: D. 8:1
- A. 1:4
- B. 4:1
- C. 1:8
- D. 8:1
Explanation
Explanation is given below:To find the ratio of their activities after six years, we can use the formula for radioactive decay: Activity = Initial activity * (1/2)^(time / half-life) Let's assume the initial activity of both substances is 1 (you can use any value since we are looking for the ratio). Now, let's calculate the activities for each substance after six years: For the substance with a half-life of 1 year: Activity after 6 years = 1 * (1/2)^(6 / 1) = 1/64 For the substance with a half-life of 2 years: Activity after 6 years = 1 * (1/2)^(6 / 2) = 1/8 Now, to find the ratio of their activities, divide the activity of the second substance by the activity of the first substance: Ratio = (1/8) / (1/64) = 8/1 = 8 So, the ratio of their activities after six years will be 8.
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