A sphere carrying charge of Q having weight w falls under gravity between a pair of vertical plates

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2. Electric Potential and Capacitance

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A sphere carrying charge of $Q$ having weight $w$ falls under gravity between a pair of vertical plates at a distance of $d$ from each other. When a potential difference $V$ is applied between the plates the acceleration of sphere changes as shown in the figure, to along line $BC$. The value of $Q$ is :-

A

$\frac{{2wd}}{V}$

B

$\frac{{wd}}{{2V}}$

C

$\frac{{wd}}{V}$

D

$\frac{{\sqrt 2 wd}}{V}$

Solution

$\tan 45^{\circ}=\frac{q E}{m g} \Rightarrow w=\frac{V}{d} q \Rightarrow q=\frac{w d}{V}$

Standard 12

Physics

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