An infinite line charge produces a field of 9 × 104 N/C at a distance of 2 cm. Calculate the linear charge density.

Given:


E = 9 × 104 NC-1


d = 2 cm


Let the linear charge density = λ Coulomb/metre



We know that, Electric field produced by a line charge with a linear charge density σ, at a distance d is given by,


…(1)


Where, λ = linear charge density.


ε0 = permittivity of free space


ε0 = 8.85 × 10-12N-1 m-2C2


d = distance


From equation (1) we have,


λ = E × 2 × π × ε0 × d


λ = 9 × 104 NC-1 × 2 × π × 8.85 × 10-12N-1 m-2C2 × 0.02m


λ = 10 μ Cm-1


The linear charge density is 10 μ Cm-1.


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