Problema Solution
Do this problem without using the exponential model:
A(t) = A sub(0) e^kt
Initially there are 400 grams of a radioactive substance on hand. If the half-life of the substance is 8 hours, give an educated guess of how much remains (approximately) after 17 hours. After 23 hours. After 33 hours.
Answer provided by our tutors
after the half-life passes, half of the material remains
17 hrs is more than two half-lives, this leaves (1/2)^2=1/4 material left, something less than 100 grams
23 hrs is less than three half-lives, this leaves (1/2)^3=1/8 material left, something more than 50 grams
33 hrs is more than four half-lives, this leaves (1/2)^4=1/16 material left, something less than 25 grams