Two point charges are lying on the $y-$axis as in the figure: $q_1=-4\mathrm{.}90C$ and $q_2=+4\mathrm{.}90C.$ They are equidistant from the point $P,$ which lies on the $x-$axis. $($a$)$ What is the magnitude of net electric field at $P?($b$)$ A small object of charge $q_0=8\mathrm{.}40C$ and mass $m=1\mathrm{.}17g$ is placed at $P.$ When it is released, what is the magnitude of its acceleration?

$($a$)$ Number

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$($b$)$ Number

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