UNIVERSE
PLANETARY INTERIORS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the uneven distribution of heat caused by conduction currents
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the uneven distribution of heat caused by convection currents
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the uneven distribution of heat caused by radiation currents
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None of the above
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Detailed explanation-1: -This is because the plates have moved as the result of convection currents in the mantle. Tectonic plates ‘float’ on the magma beneath them in the mantle. Convection currents, that occur within the molten rock in the mantle, act like a conveyor belt for the plates. Tectonic plates move in different directions.
Detailed explanation-2: -Convection currents are heat-driven cycles that occur in the air, ocean, and mantle. They are caused by a difference in temperature, often due to a differing proximity to a heat source. The difference in temperature relates directly to the density of the material, causing this effect.
Detailed explanation-3: -Tectonic plates are able to float on the mantle due to the composition of the rocks within the plates that make them less dense than the mantle. Tectonic plates move due to mantle convection, subduction and slab pull.
Detailed explanation-4: -The primary sources of thermal energy for mantle convection are three: (1) internal heating due to the decay of the radioactive isotopes of uranium, thorium, and potassium; (2) the long-term secular cooling of the earth; and (3) heat from the core.
Detailed explanation-5: -As the seafloor grows wider, the continents on opposite sides of the ridge move away from each other. The North American and Eurasian tectonic plates, for example, are separated by the Mid-Atlantic Ridge. The two continents are moving away from each other at the rate of about 2.5 centimeters (1 inch) per year.