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

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

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
Answer» `(q^2)/(8 pi in_0 a^2) (1 + 2sqrt(2))` `(2q^2)/(pi in_0 a^2)` `(q^2)/(8 pi in_0 a^2) xx 2 SQRT(2)` 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

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