Physics-
General
Easy
Question
In the figure shown an infinitely long wire of uniform linear charge density is kept perpendicular to the plane of figure such that it extends upto infinity on both sides of the paper. Find the electro static force on a semicircular ringkeptsuchthatitsgeometricalaxiscoincideswiththewire.Thesemicircularringhasauniformlinearcharge density
π ε 0 R 
4 π ε 0 
2 π ε 0 
π ε 0
The correct answer is:
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