Final answer:
It will take 30 minutes for half of the pain medicine to be left in the system.
Step-by-step explanation:
To determine how long it will take for half of the pain medicine to be left in the system, we can use the concept of half-life. The half-life of a substance is the amount of time it takes for half of the substance to decay or be eliminated. In this case, the half-life of the pain medicine is 30 minutes.
First, we need to calculate the number of half-lives it will take for half of the medicine to be left. We can use the formula:
Number of half-lives = (ln(initial amount/final amount))/ln(2)
Let's plug in the values:
Initial amount = 500 mg
Final amount = 250 mg (half of the initial amount)
Using the formula, we have:
(ln(500/250))/ln(2) = 1
So it will take 1 half-life for half of the pain medicine to be left in the system, which is equal to 30 minutes.