Electric charges and large bodies

[kenewbie]

According to my book the electric charge of large bodies like the Earth and the moon is pretty close to zero. But the Earth has poles and a magnetic field, which suggests that it isn't uniformly distributed at all. These two things SEEM contradictory to me, what is it that I am not getting?

k

 

[NanakiXIII]

Note that electric fields and magnetic fields are not the same thing, the fact that the Earth has a magnetic field has nothing to do with its net charge. Magnetism is caused by currents - moving charge - but there does not need to be a net charge for there to be a current.

Now, if the Earth had a net charge, or if the charge in the Earth was not distributed very prettily, the planet would produce an electric field.

 

[kenewbie]

That made a lot of sense thank you