Three light bulbs of $40\, W$,$60\, W$,and $100\, W$ are connected in series with a $220\, V$ source. Which one of the bulbs will glow brightest?

Two batteries $A$ and $B$, each of e.m.f. $2 \, V$, are connected in series to an external resistance $R = 1 \, \Omega$. If the internal resistance of battery $A$ is $1.9 \, \Omega$ and that of $B$ is $0.9 \, \Omega$, what is the potential difference between the terminals of battery $A$?

$A$ voltameter has a resistance of $2\,\Omega$. It is connected in series with a $10\,V$ battery and a $3\,\Omega$ resistor. The mass deposited at the cathode in a certain time is $1\,g$. Now,the voltameter and the $3\,\Omega$ resistor are connected in parallel with the battery. The increase in the mass of the metal deposited in the same time will be $...\,g$.

$A$ storage battery of $emf$ $8.0\; V$ and internal resistance $0.5\; \Omega$ is being charged by a $120\; V$ $DC$ supply using a series resistor of $15.5\; \Omega$. What is the terminal voltage of the battery during charging? What is the purpose of having a series resistor in the charging circuit?

The equivalent resistance between points $A$ and $B$ of an infinite network of resistances each of $1\,\Omega$ connected as shown,is

$A$ copper voltameter and a silver voltameter are connected in parallel. When a total charge $q$ flows through the voltameters,an equal mass of metal is deposited in each. If the electrochemical equivalents of copper and silver are $z_1$ and $z_2$ respectively,then the charge flowing through the silver voltameter is: