$A$ $DC$ source with internal resistance $R_0$ is connected to three identical resistors each of resistance $R$ as shown in the figure. If the thermal power generated in the circuit is highest,then

In the given circuit,the current flowing through the circuit is: (in $A$)

Resistances $R_1$ and $R_2$,each $60\,\Omega$,are connected in series as shown in the figure. The potential difference between $A$ and $B$ is maintained at $120\,V$. What will be the reading of the voltmeter connected between points $C$ and $D$ if the resistance of the voltmeter is $120\,\Omega$?

$A$ battery of emf $E$ has an internal resistance $r$. $A$ variable resistance $R$ is connected to the terminals of the battery. $A$ current $i$ is drawn from the battery. $V$ is the terminal potential difference. If $R$ alone is gradually reduced to zero,which of the following best describes $i$ and $V$?

An electric bulb rated as $200 \, W$ at $100 \, V$ is used in a circuit having $200 \, V$ supply. The resistance $R$ that must be put in series with the bulb so that the bulb delivers the same power is $..... \, \Omega$.

The figure shows a network of resistors and a battery. If $1 \ A$ current flows through the branch $CF$,then the $emf$ $E$ of the battery is ............... $V$.