Question

The diagrams below show interactions between charged particles. The blue particles are negatively charged, and the red particles are positively charged.

Which of the diagrams shows a correct interaction between the fields of two charged particles?

Answer 1

I can’t see the diagrams you mean — could you upload them or describe each one (A, B, C, etc.)?

Meanwhile, here are the rules you can use to decide which diagram is correct:

- Electric field lines point away from positive charges and toward negative charges. So lines should start at red charges and end at blue charges.
- Field lines never start or end in empty space (except at infinity) — they begin on positive charges and terminate on negative charges.
- Field lines never cross.
- The local field at any point is the vector sum (superposition) of the fields from each charge; lines will bend accordingly.
- For opposite charges the lines should connect from + to − (dense between them if strong attraction). For like charges the lines diverge from each charge and do not connect to the other; there is a region between like charges with weaker field or a saddle (neutral) point.
- The force on a positive test charge is in the direction of the field; the force on a negative test charge is opposite the field direction.

Using those criteria, pick the diagram that shows lines leaving red charges and entering blue charges, with no crossing and correct bending from superposition. If you upload the images or describe them, I’ll point out which one is correct.