Maths-
SAT
Easy
Question
The half-life of the radioactive isotope iodine-131 is approximately 8 days, which means that at the end of each 8-day time interval only half of the mass of the isotope that was present at the beginning of the time interval remains. Which of the following best describes how the amount of iodine-131 changes over time?
- It increases linearly
- It decreases linearly
- It increases exponentially
- It decreases exponentially
The correct answer is: It decreases exponentially
The mass of iodine isotope reduces for every 8 days.
The function is decreasing & exponential.
Thus, it is a decreasing exponentially.
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