Intro to Astronomy-Chapter 1

A circular orbit would have an eccentricity of

0

Who proposed the geocentric view that was accepted and used for more than 18 centuries?

Aristotle

In Ptolemy's geocentric model, the planet's motion along its deferent is all that is needed to understand retrograde motion.

False

Kepler relied heavily on the telescopic observations of Galileo in developing his laws of planetary motion.

False

Kepler's third law allows us to find the average distance to a planet from observing its period of rotation on its axis.

False

A fatal flaw with Ptolemy's model is its inability to predict the observed phases of

Mercury and Venus.

As you found in Part A, your weight will be greater than normal when the elevator is moving upward with increasing speed. For what other motion would your weight also be greater than your normal weight?

The elevator moves downward while slowing in speed.

According to Newton's second law, if you double the force acting on a body, the acceleration will double.

True

Compared to when it was on the surface, a satellite in an orbit whose radius is about 4 times the Earth's radius will experience about 1/16 the force due to the Earth's gravity.

True

You throw a baseball to someone; before the ball is caught, it is temporarily in orbit around Earth's center.

True

An accurate sketch of Mars's orbit around the Sun would show

a nearly perfect circle.

A major flaw in Copernicus's model was that it still had

circular orbits.

Suppose you are in an elevator. As the elevator starts upward, its speed will increase. During this time when the elevator is moving upward with increasing speed, your weight will be __________.

greater than your normal weight at rest

Tycho Brahe's contribution to Kepler's Laws of Planetary Motion were

his detailed and accurate observations of the planets' positions.

Suppose you are in an elevator that is moving upward. As the elevator nears the floor at which you will get off, its speed slows down. During this time when the elevator is moving upward with decreasing speed, your weight will be __________.

less than your normal weight at rest

Which of these was NOT seen telescopically by Galileo?

stellar parallax

If you are standing on a scale in an elevator, what exactly does the scale measure?

the force you exert on the scale