The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into tectonic plates. The Earth's lithosphere is composed of seven or eight major plates (depending on how they are defined) and many minor plates. Where the plates meet, their relative motion determines the type of boundary: convergent, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along these plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually.[2]
Tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle; the material lost is roughly balanced by the formation of new (oceanic) crust along divergent margins by seafloor spreading. In this way, the total surface of the lithosphere remains the same. This prediction of plate tectonics is also referred to as the conveyor belt principle. Earlier theories, since disproven, proposed gradual shrinking (contraction) or gradual expansion of the globe.[3]
Tectonic plates are able to move because the Earth's lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the mantle result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the spreading ridge (due to variations in topography and density of the crust, which result in differences in gravitational forces) and drag, with downward suction, at the subduction zones. Another explanation lies in the different forces generated by tidal forces of the Sun and Moon. The relative importance of each of these factors and their relationship to each other is unclear, and still the subject of much debate.
Answer:
whether it was a planet or not
Explanation:
4. Would be A
5. Would be D
I hope this helped you :)
Answer:
place, space, and scale
Explanation:
A geographer investigate issues from the view point of location according to place, space and the scale.
The place is an element of location that describes the position or the domain of occurrence of issue.
Space refers the area occupied by a body or the area where an issue is domiciled.
The scale refers to the magnitude at which an issue is view or observed.
Geographers tends to synthesize and combine these different lenses to observe and investigate an issue. Almost everything on earth can be correlated spatially using these lenses.
Answer:
Listed
Explanation:
Five common energy sources are
1. Coal and Petroleum
2. Nuclear energy
3. Geothermal power
4. Solar
5. Wind
conservation of energy is very important in current situation of energy crisis. Efficient utilization of energy sources must be one of the top priority of nations.
1. Procurement of alternate sources of energies to reduce dependence on convectional sources of energies.
2.vehicle running on electric and hydrogen fuels should developed so that sources of coal and petroleum are conserved.
3. Production of solar and wind energies should be on large scale so that their cost become cheaper and available for common people
