Expression for an electric field is given by $\vec{E} = 4000 x^{2} \hat{i} V m^{- 1}$ . The electric flux through the cube of side $20 cm$ when placed in electric field (as shown in the figure) is ______ $V cm$ .

Question

Expression for an electric field is given by E → = 4000 x 2 i ^ V m - 1 . The electric flux through the cube of side 20 cm when placed in electric field (as shown in the figure) is ______ V cm .

TestHub · Accepted Answer

Electric flux is expressed as ϕ = E → · A → = E A cos θ , here, A is area of the surface and θ is the angle between the electric field lines and the normal to A . The flux will be only from DEFG surface as on the surface OABC field is zero and for rest of the surface, area vector is perpendicular to field. So, ϕ = E A = 4000 × ( 0 . 2 ) 2 × ( 0 . 2 ) 2 = 4000 × 16 × 10 - 4 V m = 640 V cm

Physics - Elecrostatics Question with Solution | TestHub

Doubts & Discussion