Two free positive charges $4q$ and $q$ are a distance $l$ apart. What charge $Q$ is needed to achieve equilibrium for the entire system and where should it be placed form charge $q$ ?
Two free positive charges $4q$ and $q$ are a distance $l$ apart. What charge $Q$ is needed to achieve equilibrium for the entire system and where should it be placed form charge $q$ ?
- A
$Q = \frac{4}{9} q\,(negative)\, at \frac{l}{3}$ distance
- B
$Q = \frac{4}{9} q\,(positive)\, at \frac{l}{3}$ distance
- C
$Q = q\,(positive)\, at \frac{l}{3}$ distance
- D
$Q = q\,(negative)\, at \frac{l}{3}$ distance
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