1. Sep 18, 2005

### benhorris

Simple question, but i dont know where to start.

The half life of one radioactive isotope of sodium is 2.6 years. Show that its decay constant is 8.4 x 10^-9 s^-1.

Ben.

2. Sep 18, 2005

### H_man

$$T_h = \frac {ln2} { \lambda}$$

But remember to convert the time into seconds!

Last edited: Sep 18, 2005
3. Sep 18, 2005

### iNCREDiBLE

Do you know the following identity $T = \frac{ln 2}{\lambda}$, where $T$ is the half life in seconds and $\lambda$ is the decay constant.

4. Sep 18, 2005

### benhorris

Ah got it,

Thanks guys.

Was a simple error, i converted it to seconds by doing =

2.6 x 365 x 3600. And i forgot about the hours.

3600 x 24 x 365 x 2.6 = no.seconds gave the correct answer.

Silly mistake.

Last edited: Sep 18, 2005