Electric field intensity, = 3 × 10^{3} î N/C

Magnitude of electric field intensity, = 3 × 10^{3} N/C

Side of the square, s = 10 cm = 0.1 m

Area of the square, A = s^{2} = 0.01 m^{2}

The plane of the square is parallel to the y-z plane. Hence, angle between the unit vector normal to the plane and electric field, θ = 0°

Flux (Φ) through the plane is given by the relation,

Φ =

= 3 × 10^{3} × 0.01 × cos0°

= 30 N m^{2}/C