Question

A plane surface is rotated in a uniform electric field. When is the flux of the electric field through the surface maximum?

Answer 1

Answer:

When a surface is parallel to equipotential surface around a charge, the flux through the surface is maximum

Answer 2

Given:

• A plane surface is rotated in a uniform electric field.

To find:

• When is the electric flux maximum?

Calculation:

First of all, let's assume :

• Field intensity is E
• Area of plane surface is A

Now, the magnitude of flux will be :

$\boxed{ \therefore \phi = E \times A \times \cos( \theta) }$

• $\cos(\theta)$ is the angle between E vector and A vector.

For max value of flux , $\cos(\theta)$ value should be max.

$\implies \: \cos( \theta) = 1$

$\implies \: \theta = {0}^{ \circ}$

So, angle between A vector and E vector must be 0° (i.e. plane is parallel to field) for flux to be max.