PHY 205, Ch.1 HomeworkProc
Process of Science: Explaining the Motions of Planets. To ancient astronomers, the motions of the Sun, the Moon, and the stars seemed fairly simple. However, the motions of the planets, which were more complicated, were harder to account for. It was a challenge for astronomers to explain the observed motions of the planets and to relate those motions to variations in planetary brightness. Part C- The geocentric mode, in all of its complexity, survived scientific scrutiny for almost 1,400 years. However, in modern astronomy, scientists seek to explain the natural and physical world we live in as simply as possible. The complexity of Ptolemy's model was an indicator that his theory was inherently flawed. Why, then, was the geocentric model the leading theory for such a long time, even through the heliocentric model more simply explained the observed motions and brightness of the planets?
-The geocentric model conformed to both the philosophical and religious doctrines of the time -The heliocentric model did not make noticeably better predictions than the geocentric model -From Earth, all heavenly bodies appeared to circle around a stationary Earth. -Ancient astronomers didn't observe stellar parallax, which would have provided evidence in favor of the heliocentric model. [The geocentric model was the leading model for hundreds of years because it conformed to the common beliefs from observations and religious doctrine of the time. However, the heliocentric model gained widespread acceptance when astronomers obtained new evidence after the time of Copernicus. These astronomers popularized his view and helped pave the way for our current understanding of the solar system]
Think and Explain 1.24 Part A- Which of the following are scientific hypotheses? -Chlorophyll makes grass green -Tides are caused by the Moon -Earth rotates about its axis because living things need an alternation of light and darkness
Chlorophyll makes grass green Tides are caused by the Moon
Process of Science: Explaining the Motions of Planets. To ancient astronomers, the motions of the Sun, the Moon, and the stars seemed fairly simple. However, the motions of the planets, which were more complicated, were harder to account for. It was a challenge for astronomers to explain the observed motions of the planets and to relate those motions to variations in planetary brightness. Part A- Two competing models attempt to explain the motions and changing brightness of the planets: Ptolemy's geocentric model and Copernicus' heliocentric model. Sort the characteristics according to whether they are part of the geocentric model, the heliocentric model, or both solar system models.
Geocentric- This model is Earth Centered -Retrograde motion is explained by epicycles Heliocentric- This model is Sun centered. -Retrograde motion is explained by the orbital speeds of planets Both geo-and heliocentric -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. [Ptolemy's geocentric model was based on the idea that Earth is the center of the universe, while Copernicus' heliocentric model was developed around the idea that the Sun is at the center. While these two models were based on opposing ideas, they shared a common belief in uniform circular motion and the use of epicycles. However, Copernicus' heliocentric model doesn't use epicycles to explain retrograde motion like Ptolemy's geocentric model. In order to explain retrograde motion, Copernicus' uses the different orbital speeds of the planets as an explanation to the seemingly backward motion of the planets in the sky]
Process of Science: Explaining the Motions of Planets. To ancient astronomers, the motions of the Sun, the Moon, and the stars seemed fairly simple. However, the motions of the planets, which were more complicated, were harder to account for. It was a challenge for astronomers to explain the observed motions of the planets and to relate those motions to variations in planetary brightness. Part B- Copernicus' heliocentric model and Ptolemy's geocentric model were developed to provide a description of the solar system. Both models had advantages that made each an acceptably explanation for motions in the solar system during their time. Sort each statement according to whether it is an advantage of the heliocentric, the geocentric, or both.
Heliocentric- Explained planetary motions and brightness changes most simply Geocentric- Rooted in widely accepted religious beliefs regarding Earth's place in the universe Both Geo- and heliocentric -Planetary orbits and the motions based on Greek ideologies of perfect form and motion -Predicted planetary positions accurately over relatively short time periods. [The geocentric model was compelling because it adhered to religious beliefs about Earth's centrality in the universe. The heliocentric model was compelling because it provided a simpler explanation for observed motions in the solar system. Because both models adhered to the belief in the perfect form and motion, they made inaccurate predictions of planetary motions over long periods of time. since neither model made better predictions than the other, both remained viable. ]
Think and Explain 1.23 Part A- what is the penalty for scientific fraud in the science community?
The penalty for fraud is professional excommunication.
