The charge of an electron is $1.6 \times 10^{-19} \ C$. How many electrons strike the screen of a cathode ray tube each second when the beam current is $16 \ mA$?

Identify the set in which all the three materials are good conductors of electricity.

$A$ metallic conductor of non-uniform cross-sectional area is subjected to a constant potential difference. Which of the following quantities remains constant along the conductor?

The electric current flowing through a given conductor varies with time as shown in the graph below. The number of free electrons which flow through a given cross-section of the conductor in the time interval $0 \leq t \leq 20 \ s$ is

The charge flowing in a conductor changes with time as $Q(t) = \alpha t - \beta t^2 + \gamma t^3$. Where $\alpha, \beta$,and $\gamma$ are constants. The minimum value of current is:

If an electron revolves in a circular path of radius $0.5 \times 10^{-10} \ m$ at a frequency of $5 \times 10^{15} \ Hz$,the electric current in the circle is .................. $mA$. (Charge of an electron $= 1.6 \times 10^{-19} \ C$)