A very long insulating cylinder of charge of radius 2.50 cm carries a uniform linear density of 15.0 nC/m. (a) Use Gauss’s law to find an expression for the electric field a short distance r from the cylinder. (b) If you put one probe of a voltmeter at the surface, how far from the surface must the other probe be placed so that the voltmeter reads 175

r2 = 2.401557  cm

distance = 0.10 cm

Explanation:

given data

radius = 2.50 cm

density = 15.0 nC/m

voltmeter read =  175

solution

we know here potential difference that is express as

ΔV =     ...........1

so here

as here is linear charge density  

r2 = r1 ×  

r2 = 2.40 ×  

r2 = 2.401557  cm

and

here distance above surface will be

distance = r1 - r2

distance =  2.50 - 2.40

distance = 0.10 cm

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