What is the correct order of processes in the accretion of planetesimals?

What is the things about?

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.

Aand b antarctica is a north pole.  field lines enter earth near the north pole.the magnetic pole near antarctica is a north pole.compasses point toward a magnetic pole that is a north pole.field lines circle earth from east to west.a compass can lead a hiker to the geographic north pole.