Question

the picture above shows four different situations. in which situation is the greatest amount of force being applied on the negative charge.

Explanation:

Step1: Recall Coulomb's law

The force between two charges is given by $F = k\frac{q_1q_2}{r^2}$, where $k$ is the Coulomb's constant, $q_1$ and $q_2$ are the magnitudes of the two charges, and $r$ is the distance between them. The greater the product of the charges and the closer the charges are, the greater the force.

Step2: Analyze option A

The image for option A is not shown, but we analyze the others.

Step3: Analyze option B

There are two positive charges close to the negative charge. The combined effect of two positive - charges on the negative charge will create a relatively large force. The force due to each positive charge adds up vectorially.

Step4: Analyze option C

There is one positive charge at a relatively large distance from the negative charge. According to Coulomb's law, as $r$ increases, the force $F$ decreases.

Step5: Analyze option D

There is one positive charge at a distance from the negative charge, and the distance seems to be larger than in option B. So the force will be smaller than in option B.

Answer:

B