24. Electric Force & Field; Gauss' Law

When two objects are charged through friction, how do the magnitudes and signs of their electric charges compare?

Which of the following materials are efficient charge carriers ($\mathrm{conductors}$)?

In a typical metallic wire, what is the direction of conventional current relative to the motion of electrons?

A certain lightning bolt moves $30.0C$ of charge. How many units $n$ of fundamental charge $e$ is this?

A yellow sphere is repelled by a negatively charged rod and attracted to a positively charged rod. What is the sign of the charge on the yellow sphere?

In a circuit, resistors $R_1$ = $2$ $\Omega$ and $R_2$ = $4$ $\Omega$ are connected in series with a $12$ $V$ battery. What is the magnitude of the current through $R_1$?

In a circuit containing two batteries with emfs $𝑛=12 V$ and $𝑛=6 V$ connected in series with a resistor of $4 \Omega$, what is the total charge that flows through the resistor after the circuit is closed for $10 s$?

In an electric circuit, which of the following quantities is equal to the sum of the individual values for all components connected in series?

When the switch in the circuit in (figure 1) has been open for a long time and is then closed at $t=0$, what is the initial current through the resistor immediately after closing the switch?

In a circuit diagram, which symbol is commonly used to represent an electric charge?

Which of the following best describes how electricity is generated using photovoltaic cells?

In a Wheatstone bridge circuit used to measure electric charge, if resistors $r_1$, $r_2$, $r_3$, and $r_4$ are arranged in the bridge and the voltmeter reads zero when $r_3$ is adjusted, which relationship gives the value of $r_3$ in terms of the other resistances?

If the charge on the first sphere is one-quarter the charge of the second sphere, which of the following correctly expresses the charge $q_1$ on the first sphere in terms of the charge $q_2$ on the second sphere?

Which of the following conditions must be true for $electrons$ to move in a $conductor$?

What is the term for the basic unit of electric current? The basic unit of electric current is the: