In the given circuit,the potentials at points $B$,$C$,and $D$ will be:

Twelve wires of equal length and equal cross-sectional area form a cube. If the resistance of each wire is $R$,then the effective resistance between the two ends of a diagonal is:

An infinite line charge of uniform electric charge density $\lambda$ lies along the axis of an electrically conducting infinite cylindrical shell of radius $R$. At time $t=0$,the space inside the cylinder is filled with a material of permittivity $\varepsilon$ and electrical conductivity $\sigma$. The electrical conduction in the material follows Ohm's law. Which one of the following graphs best describes the subsequent variation of the magnitude of current density $j(t)$ at any point in the material?

In the adjacent circuit,a voltmeter of internal resistance $R$,when connected across $B$ and $C$,reads $\frac{100}{3} \text{ V}$. Neglecting the internal resistance of the battery,the value of $R$ is:

An electric bulb of $60 \, W, 120 \, V$ is to be connected to a $220 \, V$ source. What resistance should be connected in series with the bulb so that the bulb glows properly?

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?