Answer:
<u>Geocentric Model</u>: - this model is Earth Centered
-Retrograde motion is explained by epicycles
<u>Heliocentric Model</u>: - This model is Sun Centered
-Retrograde motion is explained by the orbital speeds of planets
<u>Both models</u>:- Epicycles and deferents help explain planetary motion
-Planets move in circular orbits and with uniform motion
-The brightness of a planet increases when the planet is closest to Earth
Explanation:
Retrograde motion is an apparent change in the movement of the planet through the sky. Ptolemy's model of the solar systems was geocentric, where the Sun, Moon, planets and start all orbit the Earth in perfectly circular orbits. However this perfectly circular orbits around the Earth did not explain the occasional retrograde motion of the planets. In the Copernicus' heliocentric model, retrograde motion of planets is naturally explained. The explanation for retrograde motion in a heliocentric model is that retrograde occurs roughly when a faster moving planet catches up to and passes a slower moving planet.
Answer:
The active volcanoes are gradually moving away from the oceanic ridge.
Explanation:
- Many oceanic volcanoes occur as long lines of the active end of volcanoes as here in the mid-oceanic ridges the plate is pushed far away from the ridge surface of the earth as these tend to move out in the direction of the movement of the plates.
- Thus the volcanoes are generally found near the active zones or regions of the tectonic plate and associated with the earthquakes occurring on the fault line or shear lines of the plates.
- Spreading of the ridges as a result of the seafloor spreading takes place and the mantel and plates from below are the driving forces that make the volcanoes and convection current that rises through the mantle pushes or spread the volcanoes to the sides like seen in the ring of fire.
<span>Their progress and wealth is highly dependent on the harvests, and
the price of grain. They probably have to import some industrial
products and if they had a bad year (weather, other catastrophies, poor
technology) they can't get the necessary amount of industrial products
in exchange for their surplus e. g. in grain. </span>
- people s increased exposure to ideas
- development of a increasingly global culture
Answer:
Erosion, compaction, nutrient imbalance, pollution, acidification, water logging, loss of soil biodiversity and increasing salinity have been affecting soil across the globe, reducing its ability to support plant life and so grow crops.
