Concepts Of Physics MCQ Edition [Volume 2]PhysicsGauss's Law
When the flux of the electric field through a closed surface is zero,
Options
- Athe charge in the surroundings of the surface must be zero
- Bthe electric field may be zero at all points on the surface
- Cthe charge enclosed within the surface must be zero
- Dthe electric field must be zero at all points on the surface
Correct answer
C. the charge enclosed within the surface must be zero
Step-by-step solution
According to Gauss's law, the net electric flux through a closed surface is given by = E d A = q_ enclosed ₀ . Given that the flux = 0 , we have q_ enclosed = 0 . This implies that the net charge enclosed within the surface must be zero. The electric field at points on the surface is the resultant field due to both enclosed and external charges. If the net enclosed charge is zero and there are no external charges, the electric field will be zero at all points on the surface. However, if there are external charges,