When a current of $2 \ A$ flows through a conductor,$80 \ J$ of heat is produced in $10 \ s$. The resistance of the conductor is ........... $\Omega$.

The current flowing through the circuit shown in the figure is ........... $A$.

Resistances of $6\, \Omega$ each are connected in the manner shown in the adjoining figure. With the current $0.5\, A$ as shown in the figure, the potential difference $V_P - V_Q$ is .............. $V$.

The battery in the diagram is to be charged by the generator $G$. The generator has a terminal voltage of $120 \ V$ when the charging current is $10 \ A$. The battery has an $emf$ of $100 \ V$ and an internal resistance of $1 \ \Omega$. In order to charge the battery at $10 \ A$ charging current,the resistance $R$ should be set at ................ $\Omega$.

Inside a superconducting ring,six identical resistors each of resistance $R$ are connected as shown in the figure. The equivalent resistance$(s)$:

The resistance between the terminal points $A$ and $B$ of the given infinitely long circuit will be