Recent content by en.yokhai

electric field, so the mass is not important...the charge is,namely the density

Homework Statement hello the question is : what is the energy needed to build a full sphere, radii R, and with density a*r The Attempt at a Solution i did it this way, i assum that i have a little ball radii r, and i want to bring an intificimal sphere width dr, and use W=Kq1dq2\r...

hey i have 2 cylinders one with r1 the second with r2. r2>r1, an cylinder capacitor. in the space between them i put 2 dielectric materials, the first in a half of the cylinder, vertical,and the second on the other side vertical. like: first- 0-180 deg second- 180-360 deg...

i'm talking about a shell

\sigma\2\epsilon sigma dividd by 2 epsilon

hey guys i'm new here...i got here with a question... i want to calculate the electric field in the middle of half sphere with raduse R , so..i made a rings out of the sphere,ds,which in fact is (2PI*R^2)sin(teta)d(teta), and tried to integrate from 0 to PI/2. i did get something...i'd...