4. A thin, very long rod uniformly charged with linear density τ charge of 10 SCLC / m. On the perpendicular to the axis of the rod, vosstavlennom end of it, to be a point charge Q = 10 nC. The distance from the end of the charge and the bar is 20 cm. Find the interaction force F charged rod and a point charge.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)