Module 2: Quiz 2 (Ch. 3 & Ch. 4)
Question 1
1 / 1 pts
Suppose a comet orbits the Sun on a highly eccentric orbit with an average (semimajor axis) dist
... [Show More] ance of 1 AU. How long does it take to complete each orbit, and how do we know?
Each orbit should take about 2 years, because the eccentricity is so large.
It depends on the eccentricity of the orbit, as described by Kepler's first law.
It depends on the eccentricity of the orbit, as described by Kepler's second law.
1 year, which we know from Kepler's third law.
Question 2
1 / 1 pts
Earth is farthest from the Sun in July and closest to the Sun in January. During which Northern Hemisphere season is Earth moving fastest in its orbit?
Spring.
Summer.
Winter.
Fall.
Question 3
1 / 1 pts
Which of these hypothetical observations (none of them are real) would force us to reconsider our modern, Sun-centered view of the solar system?
We discover an Earth-sized planet orbiting the Sun beyond the orbit of Pluto.
We discover a small planet beyond Saturn that rises in the west and sets in the east each day.
We discover that the universe is actually contracting, not expanding.
We find that we are unable to measure any parallax for a distant galaxy.
Question 4
1 / 1 pts
According to Kepler's third law (p2 = a3), how does a planet's mass affect its orbit around the Sun?
A planet's mass has no effect on its orbit around the Sun.
More massive planets must have more circular orbits.
A more massive planet must have a larger semimajor axis.
More massive planets orbit the Sun at higher average speed.
IncorrectQuestion 5
0 / 1 pts
Galileo challenged the idea that objects in the heavens were perfect by _________.
Four moons of Jupiter.
Phases of Venus.
Patterns of shadow and sunlight near the dividing line between the light and dark portions of the Moon's face.
The Milky Way is composed of many individual stars.
Question 6
1 / 1 pts
Galileo observed all of the following. Which observation offered direct proof of a planet orbiting the Sun?
Four moons of Jupiter.
Phases of Venus.
Patterns of shadow and sunlight near the dividing line between the light and dark portions of the Moon's face.
The Milky Way is composed of many individual stars.
Question 7
1 / 1 pts
The astrology practiced by those who cast predictive horoscopes can be tested by __________
comparing how often the predictions come true to what would be expected by pure chance.
asking astrologers if it works.
counting how many times the predictions come true.
polling people to find out what percentage believe their horoscopes to be accurate.
Question 8
1 / 1 pts
All the following statements are true. Which one follows directly from Kepler's third law (p2 = a3)?
Venus orbits the Sun at a slower average speed than Mercury.
Venus has a thicker atmosphere than Mercury.
Venus is more massive than Mercury.
Venus takes longer to rotate than it does to orbit the Sun.
Question 9
1 / 1 pts
How does a 12-month lunar calendar differ from our 12-month solar calendar?
It has about 11 fewer days.
Its new year always occurs in February instead of on January 1.
It uses a 23-hour rather than a 24-hour day.
It does not have seasons.
Question 10
1 / 1 pts
Only one of the statements below uses the term theory in its correct, scientific sense. Which one?
I have a new theory about the cause of earthquakes, and I plan to start testing it soon.
I wrote a theory that is 152 pages long.
Einstein's theory of relativity has been tested and verified thousands of times.
Evolution is only a theory, so there's no reason to think it really happened.
Question 11
1 / 1 pts
Suppose that a lone asteroid happens to be passing Jupiter on an unbound orbit (well above Jupiter's atmosphere and far from all of Jupiter's moons.) Which of the following statements would be true?
Jupiter's gravity would suck in the asteroid, causing it to crash into Jupiter.
There is no way to predict what would happen.
The asteroid's orbit around Jupiter would not change, and it would go out on the same unbound orbit that it came in on.
Jupiter's gravity would capture the asteroid, making it a new moon of Jupiter.
Question 12
1 / 1 pts
A rock held above the ground has potential energy. As the rock falls, this potential energy is converted to kinetic energy. Finally, the rock hits the ground and stays there. What has happened to the energy?
The energy goes to producing sound and to heating the ground, rock, and surrounding air.
The rock keeps the energy inside it in the form of mass-energy.
It is transformed back into gravitational potential energy.
The energy goes into the ground, and as a result, the orbit of the Earth about the Sun is slightly changed.
Question 13
1 / 1 pts
A net force acting on an object will always cause a change in the object's _________.
direction
speed
mass
momentum
Question 14
1 / 1 pts
Suppose you drop a 10-pound weight and a 5-pound weight on the Moon, both from the same height at the same time. What will happen?
The 5-pound weight will hit the ground before the 10-pound weight.
Both will hit the ground at the same time.
The 10-pound weight will hit the ground before the 5-pound weight.
Both weights will float freely, since everything is weightless on the Moon.
Question 15
1 / 1 pts
Which of the following best describes the origin of ocean tides on Earth?
Tides are caused by the difference in the force of gravity exerted by the Moon across the sphere of the Earth.
Tides are caused by the 23.5-degree tilt of the Earth's rotational axis to the ecliptic plane.
Tides are caused on the side of the Earth nearest the Moon because the Moon's gravity attracts the water.
The Moon's gravity pulls harder on water than on land, because water is less dense than rock.
Question 16
1 / 1 pts
The planets never travel in a straight line as they orbit the Sun. According to Newton's second law of motion, this must mean that _________.
the planets have angular momentum
the planets will eventually fall into the Sun
a force is acting on the planets
the planets are always accelerating
Question 17
1 / 1 pts
Imagine another solar system, with a star of the same mass as the Sun. Suppose a planet with a mass twice that of Earth (2MEarth) orbits at a distance of 1 AU from the star. What is the orbital period of this planet?
2 years.
6 months.
1 year.
It cannot be determined from the information given.
Question 18
1 / 1 pts
Why are astronauts weightless in the Space Station?
Because the Space Station is traveling so fast.
Because the Space Station is moving at constant velocity.
Because there is no gravity in space.
Because the Space Station is constantly in free-fall around the Earth.
Question 19
1 / 1 pts
Suppose you kick a soccer ball straight up to a height of 10 meters. Which of the following is true about the gravitational potential energy of the ball during its flight?
The ball's gravitational potential energy is greatest at the instant when the ball is at its highest point.
The ball's gravitational potential energy is always the same.
The ball's gravitational potential energy is greatest at the instant the ball leaves your foot.
The ball's gravitational potential energy is greatest at the instant it returns to hit the ground.
Question 20
1 / 1 pts
Which of the following scenarios involves energy that we would typically calculate with Einstein's formula E=mc2?
A mass raised to a great height has a lot of gravitational potential energy.
A burning piece of wood produces light and heat, therefore giving off radiative and thermal energy.
An object accelerated to a great speed has a lot of kinetic energy.
A small amount of the hydrogen in of a nuclear bomb becomes energy as fusion converts the hydrogen to helium. [Show Less]