PART A: An electric field E=160N/C at x>0 and E=-160 N/C at x<0. A cuboid of len

Question

PART A:

An electric field E=160N/C at x>0 and E=-160 N/C at x<0. A cuboid of length 20 cm and sides d=6 cm (shaded areas) has its center at the origin and its axis along the yaxis such that its ends are at y= +/- 10cm, as shown in the figure. What is the total flux through the cuboid?

PART B:

Using Gauss' law, find the net charge inside the cuboid.

PART C:

Which of the following geometric charge configuration gives rise to the electric fields? (Check all that applies.)

( ) One infinite sheet in the yz-plane of uniform positive charges at x=10 cm and one infinite sheet of the yz-plane uniform negative charges x=-10 cm.

( ) One infinite sheet in the yz-plane of uniform positive charges x=-2cm.

( ) One positive point charge at x=10 cm and one negative point chage at x=-10 cm.

( ) A dipole with the positive charge at x=10 cm and negative charge at x=-10 cm.

( ) One cylinder (radius= 6cm) of positive point charges at x=10 cm and one cylinder (radius= 6 cm) of negative point charges at x=-10 cm.

( ) One infinite sheet in the yz-plane of uniform positive charges at x=0 cm.

( ) One infinite sheet in the xy-plane of uniform positive charges at z= 0 cm.

( ) One infinite sheet in the xz-plane of uniform negative charges at y=-2 cm.

( ) One infinite sheet in the yz-plane of uniform negative charges at x=0 cm.

( ) One infinite sheet in the xz-plane of uniform positive charges at y= 0 cm.

I only have two tries per part, so please help out if you can! Thank you!

Explanation / Answer

(A)   As given in the question,

Electric field; E1 = 160 N/C, E2 = - 160 N/C

Area facing electric field: A1 = 6*6 cm^2 = 36*10^-4 m^2 = 3.6*10^-3 m^2 and A2 = - 3.6*10^-3 m^2

The flux through the cuboid can be calulated using Gauss's law,

E  = (E*dA) = E1*A1 + E2*A2

= (160*3.6*10^-3) + {(-160)*(-3.6*10^-3)} = 1.152 V*m

(B) The net charge inside the cuboid can be again calculated using Gauss's law,

E  = Q / 0  , where 0  = electric constant = 8.85*10^-12 F/m

=> Q = E*0  = 1.152* 8.85*10^-12 = 1.02*10^-11 C

(C) The correct options for the geometric charge configuration which give rise to the electric fields, could be:

Please do select those options which can create an extra electric field. Dipole can be selected as well.

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.