عدد المساهمات : 224 نقاط : 668 تاريخ التسجيل : 24/11/2011
موضوع: electric energy2 الثلاثاء يناير 10, 2012 2:05 am
The reference zero is usually taken to be a state in which the individual point (test) charges are very well separated ("are at infinite separation") and are at rest.[1]:§
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