Class 12 Physics - Chapter Electrostatic Potential and Capacitance NCERT Solutions | (a) Show that the normal component of el
(a) Show that the normal component of electrostatic field has a discontinuity from one side of a charged surface to another given by
Where 
is a unit vector normal to the surface at a point and σ is the surface charge density at that point. (The direction of 
is from side 1 to side 2.) Hence show that just outside a conductor, the electric field is σ 
(b) Show that the tangential component of electrostatic field is continuous from one side of a charged surface to another.
[Hint: For (a), use Gauss's law. For, (b) use the fact that work done by electrostatic field on a closed loop is zero.]
Electric field on one side of a charged body is E1 and electric field on the other side of the same body is E2. If infinite plane charged body has a uniform thickness, then electric field due to one surface of the charged body is given by,
Where,
= Unit vector normal to the surface at a point
σ = Surface charge density at that point
Electric field due to the other surface of the charged body,
Electric field at any point due to the two surfaces,
Since inside a closed conductor, 
= 0,
Therefore, the electric field just outside the conductor is 
(b) When a charged particle is moved from one point to the other on a closed loop, the work done by the electrostatic field is zero. Hence, the tangential component of electrostatic field is continuous from one side of a charged surface to the other
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