Linear attenuation coefficient.

[nucerl]

Why do we call the attenuation coefficient LINEAR?

I(x)=I_oexp[-µx]

why µ is called linear?

 

[blather]

Stop me when you're satisfied.

It's not μ². Like, if we looked at it on a Log plot.

 

[gneill]

Why do we call the attenuation coefficient LINEAR?

I(x)=I_oexp[-µx]

why µ is called linear?

Perhaps it's bit confusing because the equation in which it's embedded is not a linear equation The linear bit comes in when we consider that it's 'x' that is the linear distance involved -- the µ is just a coefficient. The equation provides the value of I (presumably an intensity here) with respect to a linear change in the distance x.

 

[blather]

That's true, something like "exp[x]" is not linear, but think of the logarithmic plot. When we plot this function by taking a logarithmic plot, we see that we get a linear trend. That is, the more particles we send at our attenuator, the more are absorbed. This is characterized by a coefficient (that "mu" looking guy right there) and this trend is linear. It's quite significant to find constants and linear trends in physics. It means we have quantities that describe the material.

I, on first glance in a lab class, would think that a linear trend wouldn't be had so quickly. Like, maybe it would do some sort of decay even if we plotted it on a logarithmic scale. So, I guess some other naive student at some point thought the same thing and started calling it linear. Unfortunately, lots of things in math and physics are misnamed. Take for example the "principal value of an integral." I mean, "principal" isn't even spelled correctly for the context.

More on that logarithmic plot: just take the logarithm of both sides and you'll get it right away. It looks like y=mx+b.

 

[nucerl]

That's true, something like "exp[x]" is not linear, but think of the logarithmic plot. When we plot this function by taking a logarithmic plot, we see that we get a linear trend. That is, the more particles we send at our attenuator, the more are absorbed. This is characterized by a coefficient (that "mu" looking guy right there) and this trend is linear. It's quite significant to find constants and linear trends in physics. It means we have quantities that describe the material.

I, on first glance in a lab class, would think that a linear trend wouldn't be had so quickly. Like, maybe it would do some sort of decay even if we plotted it on a logarithmic scale. So, I guess some other naive student at some point thought the same thing and started calling it linear. Unfortunately, lots of things in math and physics are misnamed. Take for example the "principal value of an integral." I mean, "principal" isn't even spelled correctly for the context.

More on that logarithmic plot: just take the logarithm of both sides and you'll get it right away. It looks like y=mx+b.

Thanks for the clarification. I'm satisfied.