Resistance and resistivity are related by a: A: factor that is dependent on the length of the material
B: proportionality constant dependent on the source of the material
C: factor that is dependent on the area of the material
D: proportionality constant dependent on the identity of the material

D

Explanation: Resistance of current in a wire is directly proportional to the length of the wire and inversely proportional to the cross - sectional area of the wire. That is,

R = (rho × L)/A

Where

L = length of the wire

A = cross sectional Area of the wire

rho = resistivity = proportionality constant which depends on the quality of the wire.

Therefore, Resistance and resistivity are related by a:

proportionality constant dependent on the identity of the material.

dopamine..

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force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach