A uniformly charged large thin plane sheet has charge . . .

Question : A uniformly charged large thin plane sheet has charge density, σ=(1/18π)×10^-15 C/m². Find the electric field at point A which is 5 cm from the sheet.

Doubt by Angad

Solution :
 

Surface charge density (σ) 

= (1/18π)×10¹⁵ C/m²

Electric Field due to uniformly charged sheet is given by 
E = σ/2ε₀

Clearly it is independent of distance from the sheet. Hence, the electric field at both the points A and B will remain same whether it is 5 cm away or 3 cm away. 

E = 10^-6 N/C

Hence, the electric field at point A which is 5 cm from the sheet is equal to 10^-6 N/C.