Consider four different charge configurations, each with a dot marked at a specific location: (A) a single point charge $q$ placed $r$ meters away from the dot, (B) two point charges $q$ and $-q$ placed symmetrically at equal distances $r$ from the dot, (C) a uniformly charged ring of total charge $Q$ with the dot at its center, and (D) a single point charge $2q$ placed $r$ meters away from the dot. In which case does the electric field at the dot have the largest magnitude?

Given a positive point charge located to the left of a dot, what is the direction of the electric field at the dot?

In ionization type detectors, what is the typical magnitude of the electric field between the two electrodes?

A point charge of $q$ is located a distance $r$ from a dot as shown in Figure 1. What is the magnitude of the electric field at the dot due to the point charge?

A uniformly charged solid ball of radius $R$ carries total charge $Q$. What is the magnitude of the electric field $E\left(r\right)$ at a distance $r$ such that $r>R$ from the center of the ball?

When a net charge $Q$ is placed on a hollow conducting sphere, how does the net charge $Q$ distribute itself?

An electron is placed at a point in an $E$lectric field as shown in figure 3. What is the direction of the force acting on the electron at this point?

A point charge of $q$ is located at a distance $r$ from a dot in vacuum. What is the magnitude of the electric field at the dot?