geomagnetic variation मीनिंग इन हिंदी

In general, electric currents within ionosphere and magnetosphere are three-dimensional, and an infinite number of current configurations fits to the geomagnetic variations observed on the ground.
with J ( in milliAmpere / meter ) the electric overhead sheet current, ?H ( in nanoTesla ) the observed horizontal component of the geomagnetic variation, and ? the electric permeability of free space.