A charge $Q$ is placed at each of the opposite corners of a square. A charge $q$ is placed at each of the other two corners. If the net electrical force on $Q$ is zero, then $\frac{Q}{q}=$ ______
A charge $Q$ is placed at each of the opposite corners of a square. A charge $q$ is placed at each of the other two corners. If the net electrical force on $Q$ is zero, then $\frac{Q}{q}=$ ______
- [AIEEE 2009]
- A
$-2 \sqrt 2$
- B
$-1$
- C
$1$
- D
$-$$\frac{1}{{\sqrt 2 }}$
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- [AIEEE 2011]
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