# Linear attenuation coefficient

1. Mar 14, 2015

### jagguy

1. The problem statement, all variables and given/known data
This i self study!
Hi, How thick should a foil made from absorber II be to give the same absoption as 1mm thick foil made from absorber I for xrays with energy 5X106

xray beam passing through an absorption material it is attenuated , this is given by

I/Io e-ax

io =initial intensity of the beam
i=intensity of beam from absorber taken as average amount of photons emerging from 1cm2
x=thickness of slab of absorbing material in cm-1
a=linear attenuation material
e=2.718

table photon energies 5X106
absorber 1 .4
absorber 2 .2

2. Relevant equations

linear attenuation coefficient=% reduced/thickness of absorber

3. The attempt at a solution

used logs to find x

tried to use linear attenuation coefficient
but really got stuck on what to do

2. Mar 14, 2015

### jagguy

I/Io= e-ax

3. Mar 14, 2015

### jagguy

I/Io =e-ax

4. Mar 14, 2015

### jagguy

i go t an answer of 2mm because ax value where a is halved so x is doubled to keep same forumla