re: #192 FemNaziBitch

ok, I understand that.

can’t you do this with geometry?

that sounds like algebra to me.

I appreciate your efforts. The thing is that the end use of all this information is nothing I’ve ever needed or wanted enough to figure out for myself. Maybe it’s just a total lack of interest instead of an inability to understand.

The area (or volume) formulas for the various classic geometric solids is pretty well known. For terms of integral calc they’re a bit like the physicists “spherical cows” since they’re uniform shapes without the fun variation found in nature.

If you want a real-world example of something that can be solved by integrals it could be something like this:

You have a railroad tankcar of cylindrical shape with rounded end caps and know dimensions (height, length, width). How can you get the volume currently in the tank car of a liquid from putting a stick into the tankcar from the top and measuring the depth of liquid in the tank.

My father, the engineer (bless his heart), fed me that one at the dinner table one night when I was a sophomore in college. I gave him an answer two years later since the solution is more than a single integral.

A decade after that I told him, “About that railcar. I go onto the site for the car leasing company, download the ‘stick table’ for the car, and go against that.” (The companies that make tank railcars publish the information correlating measured depth of liquid to volume being occupied. You can then do an additional calculation based on the specific gravity of the liquid to work out how much of it (in mass) you have as well.)

O_o gah. Trivia buried in my head still from growing up and then working with railcar freight apps for over a decade.