43Lb has a half life of 42 minutes. If you start with 100 grams, how many grams will you have after 84 minutes?
To calculate the remaining grams of 43Lb after a certain amount of time, we can use the formula for exponential decay:
N(t) = N0 * (1/2)^(t/h)
Where:
N(t) is the remaining amount after time t
N0 is the initial amount
t is the elapsed time
h is the half-life
In this case, the initial amount (N0) is 100 grams, the elapsed time (t) is 84 minutes, and the half-life (h) is 42 minutes.
Plugging in the values into the formula:
N(84) = 100 * (1/2)^(84/42)
Simplifying further:
N(84) = 100 * (1/2)^2
N(84) = 100 * (1/4)
N(84) = 25
Therefore, you will have 25 grams of 43Lb left after 84 minutes.