Solving a problem in physics section 59 paragraph 81 el

Solving a problem in physics section 59 paragraph 81 el

81. Two infinitely long threads with the same linear charge density τ = 2,0 SCLC / m2 are at a distance a = 3,0 cm. What kind of work A unit of length must be performed in order to bring together these threads up to a distance b = 1,0 cm ?

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