Question

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

Answer 1

E = 9 x 10⁴ NC^-1, r = 2 cm = 2 x 10^-2m
E = 9 x 10⁹ x \(\frac { 2λ }{ 2 }\)
λ = \(\frac{\mathrm{Er}}{9 \times 10^{9} \times 2}\) = \(\frac{9 \times 10^{4} \times 2 \times 10^{-2}}{9 \times 10^{9} \times 2}\) = 0.1µC/m