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If the charge on a body is increased by $2 \mathrm{C}$, the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is
If the charge on a body is increased by $2 \mathrm{C}$, the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is
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If the charge on a body is increased by $2 \mathrm{C}$, the energy stored in it increases by $21 \%$. The original charge on the body in coulomb is
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$20$
Energy stored, $E \propto q^2$
$\begin{aligned} \frac{E_1}{E_2} & =\left(\frac{q_2}{q_2}\right)^2 \\ \frac{100}{121} & =\left(\frac{q}{q+2}\right)^2 \\ \left(\frac{10}{11}\right)^2 & =\left(\frac{q}{q+2}\right)^2 \\ \frac{10}{11} & =\frac{q}{q+2} \\ \Rightarrow 10 q+20 & =11 q \\ q & =20 \mathrm{C}\end{aligned}$
[OBJECT END
$\begin{aligned} \frac{E_1}{E_2} & =\left(\frac{q_2}{q_2}\right)^2 \\ \frac{100}{121} & =\left(\frac{q}{q+2}\right)^2 \\ \left(\frac{10}{11}\right)^2 & =\left(\frac{q}{q+2}\right)^2 \\ \frac{10}{11} & =\frac{q}{q+2} \\ \Rightarrow 10 q+20 & =11 q \\ q & =20 \mathrm{C}\end{aligned}$
[OBJECT END
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