An electric field of intensity 3.80 kN/C is applied along the x-axis. Calculate the electric flux through a rectangular plane 0.350 m wide and 0.700 m long if the following conditions are true.

Answer: 1.55 x 10⁴ Nm²c^-1

Explanation: The electric flux, electric field intensity and area are related by the formulae below.

Φ = EAcosθ,

Where Φ = electric flux (Nm²c^-1)

E = electric field intensity (N/m²)

A = Area (m²)

θ = this is angle between the planar area and the magnetic flux

For our question E=3.80KN/c = 3800 N/c

A = 0.700 x 0.350 = 0.245m²

θ = 0° (this is because the electric field was applied along the x axis, thus the electric flux will be parallel to the area).

Hence Φ = 3800 x 0.245 x cos (0)

= 3800 x 0.245 x 1 (value of cos 0° = 1)

= 1.55 x 10⁴ Nm²c^-1

Thus the electric field is 1.55 x 10⁴ Nm²c^-1