The battery in the diagram is to be charged by the generator $G$. The generator has a terminal voltage of $120$ $\mathrm{volts}$ when the charging current is $10$ $\mathrm{amperes}.$ The battery has an $\mathrm{emf}$ of $100$ $\mathrm{volts}$ and an internal resistance of $1$ $\mathrm{ohm}.$ In order to charge the battery at $10$ $\mathrm{amperes}$ charging current, the resistance $R$ should be set at ................ $\Omega$
Medium
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The generator has a terminal voltage of $120$ volts when the charging current is $10$ amperes. Hence,
$E=V+I r=120+10(1)=130 \mathrm{V}$
Hence, in circuit
$R=\frac{E-V}{I}$
$R=\frac{130-120}{10}=1 \Omega$
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