Hi,(adsbygoogle = window.adsbygoogle || []).push({});

I'm new to the forum and came here because I could use some help.

At the moment I am really confused because I know that A = DecayConstant * N, where A is activity and N is the number of atoms before decay. Isn't the Activity is how many atoms decay after 1 second with a specific value of N? Soif the DecayConstant = 0.5, N will half each second.

So I figured if the DecayConstant is 0.5 then the half life (T1/2) is 1 second. But then I realized that contradicts the following equation:

DecayConstant = ln(2) / T1/2, if T1/2 = 1 then DecayConstant = ln(2) =/= 0.5

What have I done wrong and why isn't any of this making sense? Did I make a basic error or do I have poor understanding?

Thank you for reading and helping.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Help With Half Life

**Physics Forums | Science Articles, Homework Help, Discussion**