Interaction between two charged particles is called

I'm thinking it's 2 you are asked to explain the earth's magnetic field. which is the best reply? 1. the earth's magnetic south is similar to the north pole of a magnet. 2. the earth's core has a strong magnetic charge similar to the south pole of a magnet. 3. the earth's geomagnetic south is similar to the south pole of a magnet. 4. the earth's magnetic charge is not centered at either pole; it varies based on location.

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.

The solid that is formed and usually sinks to the bottom of a solution is the