electric power

[anzgurl]

R= pl/A
what does p and l stands for?

[ELHEK]

p is the resistivity of a material(ohms.cm). Every material normally has a set value for it. l is the length of the material.

[anzgurl]

thank you
But if i had a distance of 100 km ,do i replace "l" with d and convert it to metres?

[ELHEK]

from my experience with this equation(electronic subject) we had "l" in cm, but that was because we had "p" in ohm.cm for example

R = pl/A ----> ohms = [(ohms.cm)(cm)]/cm(^2)