$A$ wire of cross-sectional radius $r$ carries a current $I$ due to free electrons moving with a drift velocity $V$. What will be the current in another wire of the same material having half the radius and a drift velocity of $2V$?

Two wires each of radius of cross section $r$ but of different materials are connected together end to end (in series). If the densities of charge carriers in the two wires are in the ratio $1 : 4$,the drift velocity of electrons in the two wires will be in the ratio:

$A$ current passes through a wire of nonuniform cross-section. Which of the following quantities are independent of the cross-section?

$A$ metallic block has no potential difference applied across it. What is the mean velocity of free electrons in terms of $T$ (absolute temperature of the block)?

$A$ silver wire of length $3 \,m$ and of cross-sectional area $6.14 \times 10^{-6} \,m^2$ carries a current of $6 \,A$. The atomic weight and density of silver are $108 \,g/mol$ and $10500 \,kg/m^3$,respectively. $A$ silver atom contributes one free electron for conduction. The Avogadro number is $6.023 \times 10^{23} /mol$. The drift velocity of electrons in silver is close to:

Why is current not formed in solid conductors in the absence of an electric field?