2.16 (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.]
Let's assume a Rectangular loop of length l and small width b.
Now,
Line integral along the loop :
This implies
From here,
Since and are the tangential component of the electric field, the tangential component of the electric field is continuous across the surface