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Scientists think that the earths core contains iron because they have inferred that the core is iron by conducting seismic experiments. The magnetic field is also a strong clue.
Answer:
Scientists have confirmed that iron is present in the earth's core by observing the seismological data and the pattern of the earth's magnetic field.
Iron is a high-density element and is concentrated in huge amounts at the core. This iron has been present right from the time of earth's formation and has been probably there due to its gravitational force.
The seismic P-wave and S wave-wave propagation behavior within the interior of the earth depicted the presence of an inner core (solid) and an outer core (liquid) composed of iron and the temperature in this region is very high.
