Answer to Question #295944 in Electricity and Magnetism for Lhen

Question

Find the flux through the top,left,and right side of a cube of side 0.5 m when placed in a horizontal uniform electric field of 8.0N/C directed to the right.

Answer 1

Electric flux

$\phi=E.A=EAcos\theta$

Where $\theta=90°$

$E=8N/C$

$A=0.025m^2$

Top side

$\phi_t=E.A=EAcos\theta\\\theta=90\\\phi_t=0$

Bottom side

$\phi_b=E.A=EAcos\theta\\\theta=90\\\phi_b=0$

Right side

$\phi_r=EAcos\theta\\\phi_r=EAcos90=0$

Electric flux top left right side

$$\phi_{net}=\phi_t+\phi_b+\phi_r+\phi_L+\phi_f+\phi_b$$

$\phi=8\times0.25\times cos90°$

$\phi=0$