24. Electric Force & Field; Gauss' Law

Why are metals good conductors of electrical current ($I$)?

Three identical point charges $q$ are placed at three corners of a square of side $l$. What is the magnitude of the net electrostatic force experienced by the charge at the empty corner due to the other three charges?

A plastic rod is charged to $-12nc$ by rubbing. Which of the following statements is correct about the charge on the rod?

Four point charges are placed at the corners of a square of side $l$. Each corner has a charge: two adjacent corners have charge $q$ (both positive), and the other two have charge $-q$ (both negative). What is the magnitude of the net electric force on one of the positive charges due to the other three charges?

Which of the following is the primary cause of deviation error in a magnetic compass?

What is the main advantage of using a circuit breaker instead of a fuse in an electrical circuit?

Which of the following statements about electric charge is true?

In the context of electric charge, which of the following forces can be either attractive or repulsive?

Which statement best compares the function of a brush and a commutator in an electric motor?

If every minute, $120C$ of charge flow through a cross section of a wire, what is the average current in the wire?

A positive point charge is placed in a uniform electric field pointing to the right. What is the direction of the force acting on the charge?

Two point charges, $q=5.0\mathrm{nC}$ and $Q=10.0\mathrm{nC}$, are separated by a distance of $r=0.20m$ in vacuum. What is the magnitude of the force $F$ on the $5.0\mathrm{nC}$ charge?

In the context of electric generators, what is the primary function of the slip rings?

A certain cylindrical wire carries a steady current. Which of the following statements about the distribution of electric charge within the wire is correct?

If a toy car has a current of $1.5 A$ flowing through it for $10 s$, how much electric charge passes through the car during this time?