Solving a problem in physics section 44 paragraph 55 el

Solving a problem in physics section 44 paragraph 55 el

55. The electrostatic field is created positively charged with a constant surface density σ = 10 nC / m2 infinite density. What kind of work have to make in order to move the electrons along the line of tension from a distance r1 = 2 cm and r2 = 1 cm?

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