標題: AL 2題 electric fields 急救命 [打印本頁] 作者: garycoolman 時間: 09-3-4 11:40 PM
標題: AL 2題 electric fields 急救命
1. the electrics potential energyof a system of charges at infinitely large distances from one
another is taken to be zero. waht is the clectric potential energy stored in a systen of four charges, each +1C, placed at the vertices of a square with length of side 1m?
2. a uniformly charged wire has the form of a circular loop of radius b.
p1 and p2 are two points on the axis of the loop.
p1 is at a distance b from the loop centre and p2 is at a distance 2b from the loop centre .
at p1,p2, the potrntials are v1,v2 respectively .what is the 數值 of v2/v1 ?(v2 over v1)