- #1

wolf1728

Gold Member

- 37

- 5

## Main Question or Discussion Point

I know how to do half life problems and I even have a half-life calculator on my website:

http://www.1728.org/halflife.htm

However, I cannot calculate half-life when problems are stated in this form:

End Amt = Start Amt * e^-0.0391 * t (in years)

Half-life =?

I know calculus but I find it difficult understanding that kind of equation.

I believe the figure 0.0391 is the function "lambda".

So if lambda = .0391

then

half-life = ln(2) / lambda

half-life = 0.6931 / 0.0391

half-life = 17.73 years

Did I get that right?

http://www.1728.org/halflife.htm

However, I cannot calculate half-life when problems are stated in this form:

End Amt = Start Amt * e^-0.0391 * t (in years)

Half-life =?

I know calculus but I find it difficult understanding that kind of equation.

I believe the figure 0.0391 is the function "lambda".

So if lambda = .0391

then

half-life = ln(2) / lambda

half-life = 0.6931 / 0.0391

half-life = 17.73 years

Did I get that right?