The storage battery of a car has an $emf$ of $12\; V$. If the internal resistance of the battery is $0.4\; \Omega,$ what is the maximum current (in $A$) that can be drawn from the battery?

If all resistors are of $9\, \Omega$,then the reading of the ammeter is .......... $A$.

Three resistors each of $2\, \Omega$ are connected together in a triangular shape. The resistance between any two vertices will be

One end each of a resistance $r$,a capacitor $C$,and a resistance $2r$ are connected together. The other ends are respectively connected to the positive terminals of batteries $P$,$Q$,and $R$ having emfs $E$,$E$,and $2E$. The negative terminals of the batteries are then connected together. In this circuit,with steady current,the potential drop across the capacitor is:

Find the current through the $2\,\Omega$ resistance in the given circuit. (in $A$)

Two wires of resistance $R_1$ and $R_2$ have temperature coefficients of resistance $\alpha_1$ and $\alpha_2$,respectively. These are joined in series. The effective temperature coefficient of resistance is