How to find a hollow cuboid's resistance

[hackhard]

how to find a hollow cuboid's resistance between two points on same face but not lying on the edges. the line joining 2 points is parallel to the length of the cuboid.
resistivity is uniform
another related doubt - will resistance between those same points change if the cuboid is deformed (the box is crumbled)

 

[nasu]

If you are looking for a simple formula I am afraid you won't find it. The distribution of electric field and current is not uniform. And they depend on each other.
You probably need numerical methods to solve the differential equations.
Maybe some empirical formula may be found, if such is used in some industrial application.

 

[hackhard]

will resistance between those same points change if the cuboid is deformed (the box is crumbled)

 

[Tom.G]

will resistance between those same points change if the cuboid is deformed (the box is crumbled)

"Crumbled" means broken into pieces, as when a cookie is broken into crumbs. Answer: Yes
"Crumpled" means deformed or its shape changed without breaking off any pieces. Answer: No. If surfaces don't touch each other and the material is not stretched.

 

[vanhees71]

I'm not so sure about this. As the theoretical treatment is very complicated, I suggest to simply to an experiment, measuring the resistance. I guess it's not so difficult to do qualitatively with house-hold means. Just use aluminum foil and wrap a cubic box (easily tinkered with some cardboard. Also nearly any modern digital multimeter has an ohm-meter mode :-).