What Do p and l Represent in the Resistance Formula R = pl/A?

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In the resistance formula R = pl/A, "p" represents the resistivity of a material measured in ohm-centimeters, while "l" denotes the length of the material. Each material has a specific resistivity value. When using the formula, if the length "l" is given in kilometers, it should be converted to meters for consistency with the units used for resistivity. The equation maintains dimensional consistency, ensuring that resistance is calculated correctly in ohms. Understanding these variables is crucial for accurate electrical calculations.
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R= pl/A
what does p and l stands for?
 
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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.
 
thank you
But if i had a distance of 100 km ,do i replace "l" with d and convert it to metres?
 
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)
 
Thread 'Correct statement about size of wire to produce larger extension'

Thread 'Correct statement about size of wire to produce larger extension'

The answer is (B) but I don't really understand why. Based on formula of Young Modulus: $$x=\frac{FL}{AE}$$ The second wire made of the same material so it means they have same Young Modulus. Larger extension means larger value of ##x## so to get larger value of ##x## we can increase ##F## and ##L## and decrease ##A## I am not sure whether there is change in ##F## for first and second wire so I will just assume ##F## does not change. It leaves (B) and (C) as possible options so why is (C)...
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