Two point charges Q each are placed at a distance d apart. A third point charge q is placed at a distance x from mid-point on the perpendicular bisector. The value of x at which charge q will experience the maximum Coulomb's force is :
Solution
<p>Force experienced by the charge q</p>
<p>$$F = {{kQqx} \over {{{\left[ {{{\left( {{d \over 2}} \right)}^2} + {x^2}} \right]}^{{3 \over 2}}}}}$$</p>
<p>For maximum Coulomb's force for x</p>
<p>${{dF} \over {dx}} = 0$</p>
<p>On solving $x = {d \over {2\sqrt 2 }}$</p>
About this question
Subject: Physics · Chapter: Electrostatics · Topic: Coulomb's Law
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