We know from the experiment that the charge of the electron is equal by magnitude to the charge of the proton. however, every experiment has an uncertainty, and for this data the uncertainty is 10-21 i. e., we know for sure that qelqpl < 10-21, but we cannot say purely from the experimental data that it is strictly zero). if the charge of the electron was actually slightly different from the charge of the proton within this uncertainty, could it generate the magnetic field of the earth? hint: assume that due to this slight difference the earth is uniformly charged. pick the element from the periodic table you think is most common on earth (or take the hydrogen for the simplicity, although of course it is not the hydrogen that is most common). estimate the number of electrons. assume that it is equal to the number of protons. find the total charge of the earth. assuming it to be uniformly distributed, find the magnetic dipole moment using the pre- vious part of the problem. find the magnetic field on the pole, generated by such magnetic moment. compare it with the actual field of the earth.