What Are the Correct Units for p in the Equation R=pl/A?

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The equation R = ρl/A is used to determine the resistivity (ρ) of a material. Rearranging the equation gives ρ = RA/l. The units for resistance (R) are ohms, which can be expressed as m²kgS⁻³A⁻². The derived units for resistivity (ρ) are confirmed to be ohm-metre, equivalent to m³kgS⁻³A⁻². Thus, the correct units for resistivity are established as m³kgS⁻³A⁻².
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Homework Statement



rearrange to make p the subject then work out the units for p

R - resistance or wire
A - area in m2
l - length

Homework Equations



R=pl/A


The Attempt at a Solution



p = AR/l

(m2 x m2kgS-3A-2)/m

Resistance is ohms which is m2kgS-3A-2 I think.

p=m3kgS-3A-2
 
Last edited:
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Yes, your working is right. The units for resistivity is the ohm.metre or m3kgs-3A-2
 

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