We divide the thin rectangular sheet in small parts of height b and length dr. All these sheets are parallel to b. The infinitesimal moment of inertia of one of these small parts is

where

Now we find the moment of inertia by integrating from

to

The moment of inertia is

(from (-a/2) to

(a/2))
Well sorry but this is the wrong language.
Answer:
<h3>It's called Resistance! </h3>
Explanation:
If the ratio is constant over a wide range of voltages, the material is said to "ohmic" material.
Hope it helps!