Question

Electric flux density in electric field is referred to as

(a) Number of flux lines

(b) Ratio of flux lines crossing a surface and the surface area

(c) Direction of flux at a point

(d) Flux lines per unit area

This question was posed to me in semester exam.

My question is from Electric Field Density in division Electrostatic Fields of Electromagnetic Theory

Answer 1

The correct answer is (b) Ratio of flux lines crossing a surface and the surface area

To explain I would say: Electric flux density is given by the ratio between number of flux lines crossing a surface normal to the lines and the surface area. The direction of D at a point is the direction of the flux lines at that point.