What is the magnetic field?

Your reasoning is correct.

I did the math and got.

4.7619047619e-6 = 2x 10^-7/.042

Electric and magnetic fields (EMFs) are invisible lines of force that represent the boundary and the intensity that occur between objects with potential difference or voltage (so called electric field) and that surround object with electric currents flow (so called magnetic field). In some case, electric and magnetic field can be defined together as electromagnetic fields or electromagnetic wave. Electric and magnetic fields (EMFs) are invisible lines of force that represent the boundary and the intensity that occur between objects with potential difference or voltage (so called electric field) and that surround object with electric currents flow (so called magnetic field). In some case, electric and magnetic field can be defined together as electromagnetic fields or electromagnetic wave. earth’s magnetic field, sun’s rays, lightning, gamma rays, etc. & man made he most basic difference between ionized and nonionized matter is the ability to carry electric current. This ability is also the reason why virtually all the matter in the universe is—and presumably has always been—magnetized. The presence of the magnetic field has important dynamical consequences since the magnetic force can locally be much greater than the gravitational force. The ability of carrying current, which is the basis for the magnetization, is a property that is still not well known in the case of cosmical plasma. It can be different by many powers of ten from what classical theories predict. Imagine a loop of a conductor, where the loop has a certain area. Then imagine a magnetic field flowing within the loop. Multiply the area of the loop times the strength of the field and you get some sense of the amount of magnetic strength within the loop (you actually have to do a vector multiplication, If the amount of magnetic strength within this loop changes -- either through a change in the magnetic field OR in the area within the loop -- an electromotive force (EMF) is created within the loop. It turns out that EMF, potential difference, and voltage are all pretty much the same thing. The effect of the change of magnetic strength within the loop is to cause a current to be created within the loop. This is pretty much what happens with an electric generator; a loop is forced to spin while within a magnetic field, thus generating a voltage. The potential difference between two points is the measure of the amount of energy necessary to move a unit charge between those two points. If there is a constant electric field (say, between two charged plates), there is a change in energy in moving a charge within that field. The electric field intensity does not change as the charge is moved, but the energy level does; and thus, there is a potential difference. A potential difference CAN arise due to a change in the electric field intensit