Question 635: Electrostats & Capacitance

Question

Two charges, each equals to $$q,$$ are kept at $$x=-a$$ and $$x=a$$ on the $$x$$-axis. A particle of mass $$m$$ and charge $${q_0} = {q \over 2}$$ is placed at the origin. If charge  $${q_0}$$ is given a small displacement $$\left( {y <  < a} \right)$$ along the $$y$$-axis, the net force acting on the particle is proportional to

Accepted Answer

$$ \Rightarrow {F_{net}} = 2F\,\cos 	heta $$
$${F_{net}} = {{2kq\left( {{q \over 2}} ight)} \over {{{\left( {\sqrt {{y^2} + {a^2}} } ight)}^2}}}.{y \over {\sqrt {{y^2} + {a^2}} }}$$
$${F_{net}} = {{2kq\left( {{q \over 2}} ight)y} \over {{{\left( {{y^2} + {a^2}} ight)}^{3/2}}}} \Rightarrow {{k{q^2}y} \over {{a^3}}}$$
S0, $$F \propto y$$

Answer

$$y$$

Answer

$$-y$$

Answer

$${1 \over y}$$

Answer

$$-{1 \over y}$$

Electrostats & Capacitance

Two charges, each equals to $q, are kept at x=-a and x=a on the x-axis. A particle of mass m and charge {q_0} = {q \over 2} is placed at the origin. If charge {q_0} is given a small displacement \left( {y < < a} \right) along the y$-axis, the net force acting on the particle is proportional to

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