It was believed that the magnetic field to be generated deep down in the Earth's core. But the truth is the flow of liquid iron generates electric currents, which produces magnetic fields.
But the truth is no one really knows for certain so the only thing we know is that the spin of the earth is the cause of its magnetic field
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The literacy rate controls the growth of our country I think just kidding bi just want some points so I decided to answer your prob
Some molecules are too big they cannot diffuse through the membrane, for example starch (glucose) molecules.
