Question

find the flux through the surface​

Answer 1

Solution :

Given :-

A point charge (+q) is placed at a distance of 4R/3 from the centre of a disc.

Radius of disc = R

To Find :-

Electric flux associated with the disc.

Concept :-

This question is completely based on concept of Gauss law.

Calculation :-

▪ Here solid angle (S) = 2π(1-cosα)

• S = 2π(1 - 4/5)
• S = 2π/5 sr

As per Gauss law, We know that...

▪ Flux through 4π sr = q/ε

▪ Flux through 2π/5 sr = (?)

→ Φ = (2π/5 × q/ε) ÷ 4π

→ Φ = (q/5ε) ÷ 2

→ Φ = q/10ε

✒ Option-A) is correct !!