24. Electric Force & Field; Gauss' Law

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?

Three point charges of equal magnitude $q$ are placed at the corners of an equilateral triangle of side length $a$. What is the magnitude of the net force experienced by any one of the charges due to the other two?

Which of the following statements correctly describes the relationship between electric charge $q$ and electric current $I$?

Which of the following is not an advantage of an $AC$ arc welding machine?

Two point charges are separated by a distance of $25.0\mathrm{cm}$. If the charges are $\mathrm{+2.0}\mathrm{\mu C}$ and $-3.0\mathrm{\mu C}$, what is the magnitude of the electrostatic force between them? (Use $k=8.99\times {10}^{9}N·m^2·C^{-2}$)

In residential electrical systems, what is typically the highest short circuit current that can occur at the main service panel ($I\_\{\mathrm{sc}\}$)?

Why is electric charge usually transferred by $electrons$ rather than by $protons$?

An electromagnet produces a magnetic field as the result of $I$ flow in a conductor.

When a capacitor of capacitance $C$ is connected across a battery of voltage $V$, how much charge flows through the battery as the capacitor is being charged?

Which of the following is an example of an electric force acting at a distance?

Two parallel metal disks of radius $R$ are separated by a distance $d$ in vacuum and carry equal and opposite charges $Q$. What is the maximum potential difference that can be established between the disks before electrical breakdown of air occurs, given the breakdown electric field strength is $E_{\max }$?

An object has $4$ positive charges and $2$ negative charges. What is its total charge?

The negative or positive pole of an electric current is referred to as the _____.

Which of the following devices uses $\mathrm{electric} \mathrm{current}$ as part of its normal operation?