# I Linear attenuation coefficient

1. Feb 12, 2018

### Anupama

Is linear attenuation coefficient a constant for a given material or will it depend on the thickness of the material?

2. Feb 12, 2018

It is "per unit thickness." To me, that implies that it is independent of the thickness of the material.

3. Feb 12, 2018

### CWatters

-1

"per unit thickness" usually means the attenuation per meter, or per foot of thickness depending on the units.

You have to scale it to the actual thickness you are using.

So for example if you had insulation rated at 1W per degree C per square meter per unit thickness but you were only using a sheet 0.1m thick, then the loss would be 10W per degree C per square meter.

4. Feb 12, 2018

### gleem

Attenuation of what?

5. Feb 12, 2018

### ChrisVer

you mean 0.1W ?

6. Feb 12, 2018

### CWatters

No. The thinner the insulation the more power leaks through it. If 1W leaks through a unit thickness (1m) then ten times as much (10W) leaks through a 0.1m thick layer.