Chapter 3

From Kepler's third law, an asteroid with an orbital period of 8 years lies at an average A)2 astronomical units. B)4 astronomical units C)8 astronomical units. D)16 astronomical units. E)It depends on the asteroid's mass.

4 astronomical units

Which of the following statements about scientific theories is not true? A)A theory cannot be taken seriously by scientists if it contradicts other theories developed by scientists over the past several hundred years. B)A theory is a model designed to explain a number of observed facts. C)If even a single new fact is discovered that contradicts what we expect according to a particular theory, then the theory must be revised or discarded. D)A theory must make predictions that can be checked by observation or experiment. E)A theory can never be proved beyond all doubt; we can only hope to collect more and more evidence that might support it.

A theory cannot be taken seriously by scientists if it contradicts other theories developed by scientists over the past several hundred years.

Kepler's third law, p2 = a3, means that A)a planet's period does not depend on the eccentricity of its orbit. B)all orbits with the same semimajor axis have the same period. C)the period of a planet does not depend on its mass. D)planets that are farther from the Sun move at slower average speeds than nearer planets.(wrong) E)All of the above are correct.

All of the above are correct.

When Copernicus first created his Sun-centered model of the universe, it did not lead to substantially better predictions of planetary positions than the Ptolemaic model. Why not? A)Copernicus misjudged the distances between the planets. B)Copernicus misjudged the speeds at which the planets orbit the Sun. C)Copernicus placed the planets in the wrong order going outward from the Sun. D)Copernicus placed the Sun at the center but did not realize that the Moon orbits Earth. E)Copernicus used perfect circles for the orbits of the planets.

Copernicus used perfect circles for the orbits of the planets.

At the Sun Dagger in New Mexico, a dagger-shaped beam of sunlight pierces a spiral A)every day at noon. B)at noon on the summer solstice C)at sunset on the spring equinox. D)at noon on the day of full Moon each month. E)during the totality of a total solar eclipse.

at noon on the summer solstice

How did Eratosthenes estimate the size of Earth in 240 B.C A)by observing the duration of a solar eclipse B)by measuring the size of Earth's shadow on the Moon in a lunar eclipse C)by comparing the maximum altitude of the Sun in two cities at different latitudes D)by sending fleets of ships around Earth E)We don't know how he did it since all his writings were destroyed

by comparing the maximum altitude of the Sun in two cities at different latitudes

The astrology practiced by those who cast predictive horoscopes can be tested by A)asking astrologers if it works B)asking astronomers if it works. C)counting how many times the predictions come true. D)comparing how often the predictions come true to what would be expected by pure chance. E)polling people to find out what percentage believe their horoscopes to be accurate.

comparing how often the predictions come true to what would be expected by pure chance.

The path that led to modern science emerged from ancient civilizations in which part of the world? A)Central and South America B)the Mediterranean and the Middle East C)North America D)China E)Southern Asia

the Mediterranean and the Middle East

The names of the seven days of the week are based on the A)seven naked-eye objects that appear to move among the constellations. B)seven planets closest to the Sun. C)even brightest stars in the prominent constellation Orion. D) most popular Norse gods. E) seven largest constellations of the ancient world

the seven naked-eye objects that appear to move among the constellations

Why did Ptolemy have the planets orbiting Earth on "circles upon circles" in his model of the universe? A)to explain why more distant planets take longer to make a circuit through the constellations of the zodiac B)to explain the fact that planets sometimes appear to move westward, rather than eastward, relative to the stars in our sky C)to explain why the Greeks were unable to detect stellar parallax (wrong) D)to properly account for the varying distances of the planets from Earth E)to explain why Venus goes through phases as seen from Earth

to explain the fact that planets sometimes appear to move westward, rather than eastward, relative to the stars in our sky