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Question
Four point charges Q, q, Q and q are placed at the corners of a square of side 'a' as shown in the figure.
Find the
1) resultant electric force on a charge Q, and
2) potential energy of this system.
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Solution
1) `F_"net" = "KQ"^2/(2a^2) + (sqrt2KQq)/a^2`
2) Potential energy of the system = `(4KQq)/a + "KQ"^2/(sqrt2a) + (Kq^2)/(sqrt2a)`
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