24. Electric Force & Field; Gauss' Law

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

In electrostatics, if a conductor is placed in an external electric field and is in equilibrium, what is the total surface charge $q_{\mathrm{ext}}$ on the exterior surface of the conductor?

Which device is typically used to produce alternating current?

Two point charges are placed on the x-axis: charge $q_1$ at $x=0$ and charge $q_2$ at $x=d$. If both charges are positive, what is the direction of the net electric force on $q_1$ due to $q_2$?

In the context of electric charge and semiconductor devices, what type of bias is applied to a $pn$ junction if the cathode is positive with respect to the anode?

Which of the following statements about the flow of electricity through air is correct?

Two point charges, $q=8.0\mathrm{nC}$ and $Q=12.0\mathrm{nC}$, are separated by a distance of $r=0.50m$ in vacuum. What is the magnitude of the force $F$ on the $8.0\mathrm{nC}$ charge?

A current of $0.50A$ flows through a resistor of $820\Omega$. What is the voltage across the resistor?

Which of the following factors does not affect the resistance of a conductor?

Two point charges are fixed on the y-axis at positions $(0,a)$ and $(0,-a)$. If both charges have magnitude $q$ but opposite signs, what is the direction of the electric field at the origin?

In a simple circuit consisting of a battery of emf $E$ and an external resistor $R$, the battery current $i$ is:

Which term describes the process in which electric charge is redistributed within a material, causing one side to become $\mathrm{positive}$ and the other $\mathrm{negative}$?

A thundercloud has a radius of $R$ and is at a potential of $V$ relative to the ground. If the breakdown electric field of air is $E_{\text{break}}$, what is the approximate total charge $q$ on the cloud when the breakdown of the surrounding air is reached?

Four identical point charges, each of charge $q$, are placed at the corners of a square of side $a$. What is the magnitude of the net electric force experienced by one of the charges due to the other three?

An insulating sphere of radius $a$, centered at the origin, has a uniform volume charge density $\rho$. What is the total charge contained within the sphere?