24. Electric Force & Field; Gauss' Law

Which of the following best differentiates between direct current $\mathrm{DC}$ and alternating current $\mathrm{AC}$?

After a switch in a circuit containing a capacitor of capacitance $C$ and initially uncharged is closed and connected across a battery of emf $V$, how much charge flows through the switch until the capacitor is fully charged?

For the circuit above, if a resistor of resistance $R$ is connected in series with a battery of emf $V$, what is the electric charge that flows through the resistor in time $t$?

Which of the following is an example of static electricity?

Which best explains why an electric toaster is considered a resistor?

Four point charges of equal magnitude $q$ are placed at the corners of a square of side $a$. If all charges are positive, what is the magnitude of the net electric force on one of the charges due to the other three?

How many coulombs of electric charge are contained in $1$ $A$-$h$?

Which term describes the transfer of electric charge between two objects that are not in direct contact with each other?

If two point charges $q_1$ and $q_2$ are located at distances $r_1$ and $r_2$ from a third charge $q$, and all three charges are aligned along a straight line, what is the magnitude of the total electric force that $q_1$ and $q_2$ exert on $q$?

In the context of electromagnetic waves generated by an oscillating electric charge, what does the frequency $f$ of the emitted electromagnetic field represent?

Why are metals generally good conductors of electric current $I$?

What is a very important difference between $\mathrm{electric} \mathrm{charges}$ and $\mathrm{magnetic} \mathrm{poles}$?

Which of the following instruments is used to measure the resistance to electrical current ($R$)?

Given that the wires in (figure 1) all have the same resistance, but their lengths and radii are different as noted, which of the following relationships between length $L$ and radius $r$ must be true for a wire to have the same resistance as the others?

Which of the following units is used to measure the electrical resistance of a circuit?