Question

why cant we say electric field is produced by the earth instead of magnetic field ?

Answer 1

The earth has both. The magnetic field is to do with the great lump of iron at the earth's core. But there is also an electric field between the earth's surface and the different layers of the atmosphere.

Answer 2

but iron core inside earth is melted and at hgh temperature at that temperature curies law is not applicable my teacher said ! so that reason for magnetic field is not valid !

Answer 3

(Curie's Law - that rings a very faint bell.) I think that it is fair to say that we don't absolutely understand and have explained the earth's magnetic field. It is certainly not the case that the iron core of the planet is just a huge magnet. So your teacher is quite right about that. But the core is made up of a solid iron centre and an outer layer of molten iron (and other metals, notably nickel). So both elements of the core electrically conductive and they move in relation to each other and to the outer layers of the planet. So you have all the necessary features for generating an electromagnetic field. This anyway is the generally accepted theory. NB Not all of the planets have a magnetic field, although I can no longer remember which ones (two?) do not.

Answer 4

oh ok =)

Answer 5

ANd if anyone is interested the BBC just had a program which sets all this out and is bang up to date with the latest science about the core of the earth and the magnetic field

http://www.bbc.co.uk/iplayer/episode/b0148vph/Horizon_20112012_The_Core/