The potential difference across the $40\,\Omega$ resistor in the given circuit is ............ $V$.

$A$ set of $n$ equal resistors,each of value $R$,are connected in series to a battery of emf $E$ and internal resistance $R$. The current drawn is $I$. Now,the $n$ resistors are connected in parallel to the same battery. The current drawn from the battery becomes $10I$. The value of $n$ is:

Each element in the finite chain of resistors shown in the figure is $1\,\Omega $. $A$ current of $1\, A$ flows through the final element. Then what is the potential difference $V$ across input terminals of the chain (in $,V$)?

In the circuit shown below,the resistances are given (in $\Omega$) and the battery is assumed ideal with an electromotive force (emf) equal to $3.0 \, V$. The resistor that dissipates the most power is

If $96500 \ C$ of charge deposits $1 \ g$ of a substance,how much time will it take to deposit $20 \ mg$ of copper from a copper sulfate solution using a current of $0.15 \ A$?

Model a torch battery of length $l$ to be made up of a thin cylindrical bar of radius $a$ and a concentric thin cylindrical shell of radius $b$,filled in between with an electrolyte of resistivity $\rho$ (see figure). If the battery is connected to a resistance of value $R$,the maximum Joule heating in $R$ will take place for: