Question

Descerib the origin and evolution of the earth and give the explanation of interior of the earth in hindi

Answer 1

Origin: the Big Bang was a supernova explosion that released huge amounts of gas and dust. These gases and dust condensed into nebulae, including the one that formed Earth. The force of gravity caused this cloud of gas to condense into a protostar, and then into a main sequence star when Earth started to produce its own nuclear fuel (by fusing hydrogen nuclei into helium nuclei). This outward pressure produced balanced the compressing force due to gravity so the Earth did not shrink. We are currently in our main sequence stage.

Interior (starting from the crust):
Asthenosphere (upper mantle) - 5% partially molten: reduces friction in plates
Lower mantle - molten rock. Hot so causes convection currents which pull tectonic plates round (as it is a liquid that flows between the hotter outer core and the cooler asthenosphere).
Outer core - magnetic iron-nickel alloy. Liquid as there is not enough heat and pressure to solidify it.
Inner core - magnetic iron-nickel alloy. Solid as there is enough heat and pressure. It is 5400 degrees celcius; the same temperature as the surface of the sun.

Hope that helps!