Question 933: Electrostats & Capacitance

Question

A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium if q is equal to

Accepted Answer

Let the distance between given changes be 2x
In equilibrium, $$\left| {{{\overrightarrow F }_{AB}}} \right| + \left| {{{\overrightarrow F }_{AC}}} \right| = 0$$
So, $$\left| {{F_{AB}}} \right| =  - \left| {{F_{AC}}} \right|$$
$${1 \over {4\pi {\varepsilon _0}}}{{{Q^2}} \over {4{x^2}}} =  - {1 \over {4\pi {\varepsilon _0}}}{{Qq} \over {{x^2}}}$$
$$ \Rightarrow q =  - Q/4$$

Answer

$$-$$Q/4

Answer

Q/4

Answer

$$-$$Q/2

Answer

Q/2

Electrostats & Capacitance

A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium if q is equal to

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