Four charges of +q, -q, +q and +q are placed at the corners A, B, C and D of a square. The resultant force on the charge at D is

Four charges of +q, -q, +q and +q are placed at the corners A, B, C an

1.	Four charges of +q, -q, +q and +q are placed at the corners A, B, C and D of a square. The resultant force on the charge at D is
Answer» `(q^(2))/(4PI epsi_(0) a^(2)) (sqrt2 - (1)/(2))` `(2Q^(2))/(PI epsi_(0)a^(2))` `(q^(2))/(8pi epsi_(0)a^(2)) 2 sqrt2` zero Answer :A

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Four charges of +q, -q, +q and +q are placed at the corners A, B, C and D of a square. The resultant force on the charge at D is

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