# Homework Help: How you could find E'/E at the min of 180 degrees

1. Apr 4, 2005

### dranger35

From the Comptom Scattering formula, you get
(E-E')/E E' = (1/mc^2)(1-cos@).

Can someone tell me how you could find E'/E at the min of 180 degrees. I've tried using the conjugate, and other methods, but I cant get E'/E out of it. I must be doing something wrong. Thanks.

2. Apr 4, 2005

### dextercioby

$$\frac{1}{E'}-\frac{1}{E}=\frac{2}{mc^{2}} \Rightarrow \frac{E'}{E}=\frac{mc^{2}}{2E+mc^{2}}$$

Daniel.

3. Apr 5, 2005

### dranger35

Wait

.... is the answer just E'/E = mc^2/(2E + mc^2) or
mc^2/(2E + mc^2) (1- cos@).

4. Apr 5, 2005

### dextercioby

You said about $180 \mbox{deg}$,right...?I assumed you did,and used this fact.How would my formula change,if,instead of that particular value for the scattering angle,you'd use the general case?
It's not difficult,it's simple algebra.

Daniel.