UNIVERSE
PLANETARY INTERIORS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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solid all the way to the center of the inner core
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solid, then liquid to the center of the inner core
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solid, then liquid, then solid again to the center of the inner core
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solid, then liquid, then gaseous to the center of the inner core
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Detailed explanation-1: -The outer core is not under enough pressure to be solid, so it is liquid even though it has a composition similar to that of the inner core. The temperature of the outer core ranges from 4, 300 K (4, 030 °C; 7, 280 °F) in the outer regions to 6, 000 K (5, 730 °C; 10, 340 °F) closest to the inner core.
Detailed explanation-2: -In the 20th century, geoscientists discovered an increase in the velocity of p-waves, another type of body wave, at about 5, 150 kilometers (3, 200 miles) below the surface. The increase in velocity corresponded to a change from a liquid or molten medium to a solid. This proved the existence of a solid inner core.
Detailed explanation-3: -Evidence for a fluid outer core includes seismology which shows that seismic shear-waves are not transmitted through the outer core. Although having a composition similar to Earth’s solid inner core, the outer core remains liquid as there is not enough pressure to keep it in a solid state.
Detailed explanation-4: -The lithosphere is the rocky outer part of Earth. It is made up of the brittle crust and the top part of the upper mantle. The lithosphere is the coolest and most rigid part of Earth.