I'm trying to solve problems about magnetic fields of electric currents induced by charged particles and wires. Most of these problems require the right hand rule, which I don't really understand. All I know is your thumb points in the direction of the current and your fingers curl in the direction of the magnetic field. I don't understand how to tell if the magnetic field is going into the page or out of the page based on this. Question 1: The figure shows 2 charged particles moving in opposite directions. What is the direction of the magnetic field at point P? I attempted to copy the figure but the forum keeps editing it so I'll describe it: there are 2 positive particles separated by a distance (d). One is moving to the right, the other to the left. Halfway between the particles is point P (kind of like below, the plus signs represent positive particles with P halfway between). (+) l l P l l (+) Answer: Both particles make magnetic fields that point into the page. I know this is the correct answer, but I don't get how to do this? How can you tell if the magnetic field is into or out of the page?