OpenStudy (anonymous):

In 5 days a 10.0mg sample of radioactive material decays to 3.5mg. based on this information what is the half life?

7 years ago
OpenStudy (shadowfiend):

Hm. Do you have an exponential decay function to work with?

7 years ago
OpenStudy (anonymous):

Current quantity = original quantity times e raised to the power (elaspsed time / half life), if I remember correctly, or \[Q=Q _{0}e ^{t/h}\]. Plug in and solve for half life; you have everything else you need.

7 years ago
OpenStudy (anonymous):

Oops. I think my exponent is missing a k, specifically -ln(2). So the correct exponent, if I'm right, is e^(-t ln2)/h

7 years ago