24. Electric Force & Field; Gauss' Law

In a circuit containing three resistors connected in parallel to a single voltage source, how many potentially different currents can exist in the circuit?

In the circuit shown in (figure 1), a capacitor is connected in series with a resistor and a battery. The switch has been closed for a long time prior to $t=0$, allowing the circuit to reach steady state. What is the charge stored on the capacitor just before $t=0$?

Which of the following best describes an $RC$ circuit in the context of electric charge?

For a long hollow cylindrical conductor carrying a steady current, what is the electric field inside the hollow region (but not inside the conducting material itself)?

A large electroscope is made with “leaves” that are 66-cm-long wires with tiny 21-g spheres at the ends. When charged, nearly all the charge resides on the spheres. If the wires each make a 26° angle with the vertical (Fig. 21–58), what total charge Q must have been applied to the electroscope? Ignore the mass of the wires.

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?