If the electric flux through a circular area is 5.0 Nm2/C, what is the electric flux through a circle of double the diameter assuming the orientations of the circles are the same and the electric field is uniform?

1.25 Nm²/C

Explanation:

Flux = quantity / (unit area)

Electric flux = Electric field / (unit area)

Let the initial area over which the flux is initially expressed be A

5 = Electric field/A

Electric field = 5A N/C

If this same electric field is expressed over an area double the initial diameter of the initial circle, the area of new circle = 4A.

This is because Area is proportional to the square of diameter. A = kD², so area of new circle with diameter 2D, A₁ = k (2D) ² = 4kD² = 4A

New electric flux = 5A/4A = 5/4 = 1.25 Nm²/C