99 Percentile Qs Bank for JEE MainPhysicsElectrostatics
A hollow cylinder has a charge q coulomb within it. If ϕ is the electric flux in units of Vm associated with the curved surface B , the flux linked with the plane surface A in units of Vm will be
Options
- Aq 2 ε 0
- Bϕ 3
- Cq ε 0 - ϕ
- D1 2 q ε 0 - ϕ
Correct answer
D. 1 2 q ε 0 - ϕ
Step-by-step solution
Let ϕ A , ϕ B and ϕ C are the electric flux linked with A , B and C . According to gauss theorem, ϕ total = ∑ q ε 0 ϕ A + ϕ B + ϕ C = q ε 0 Since ϕ A = ϕ C , ∴ 2 ϕ A + ϕ B = q ε 0 or 2 ϕ A = q ε 0 - ϕ B or 2 ϕ A = q ε 0 - ϕ (Given ϕ B = ϕ ) ∴ ϕ A = 1 2 q ε 0 - ϕ