Intro to Astronomy: Hw Questions First Exam
A planet with twice Earth's mass orbiting at a distance of 1 AU from a star with the same mass as the Sun.
1 year
A planet with the same mass as Earth orbiting at a distance of 1 AU from a star with four times the Sun's mass.
6 months
Which person is weightless?
A child in the air as she plays on a trampoline.
Consider the statement "There's no gravity in space." This statement is
Completely false
According to the law of universal gravitation, what would happen to Earth if the Sun were somehow replaced by a black hole of the same mass?
Earth's orbit would not change.
Why is a sunflower yellow?
It reflects yellow light.
Is Polaris a circumpolar star in San Diego 's sky? Choose the correct explanation.
Polaris is circumpolar because it never rises or sets in San Diego 's sky.
For people in Buenos Aires (35 degrees S), spring occurs on which day?
Sept 21
What are your latitude and longitude in San Diego?
The latitude in San Diego is 32∘N and the longitude is about 117∘W
Where does the north (or south) celestial pole appear in your sky?
The north celestial pole appears in San Diego 's sky at an altitude of 32 ∘ in the direction due north.
Radio waves are:
a form of light.
The Hubble Space Telescope obtains higher-resolution images than most ground-based telescopes because it is:
above Earth's atmosphere
If the Moon were closer to Earth, high tides would
be higher than they are now.
The set of spectral lines that we see in a star's spectrum depends on the star's:
chemical composition.
Do you think Northern Hemisphere summers on Mars are warmer or colder than Southern Hemisphere summers (when the Southern Hemisphere is tilted towards the Sun, Mars is about 20% closer to the Sun than when the Northern Hemisphere is tilted toward the Sun)?
colder
If the Earth did not have a tilt, the weather during June in Colorado would be:
colder
If the Earth were tilted 40 degrees, winters in Colorado would be:
colder
A star whose spectrum peaks in the infrared is:
cooler than our Sun.
Why are summers in North America warmer than winters in North America?
during summer, North America receives more direct sunlight than it does in winter.
When we see Saturn going through a period of apparent retrograde motion, it means
earth is passing Saturn in its orbit, with both planets on the same side of the Sun.
To make a rocket turn left, you need to:
fire an engine that shoots out gas to the right.
How much greater is the light-collecting area of a 6-meter telescope than a 3-meter telescope?
four times
When is the Sun in the northern part of the sky at noon for people who live on the equator?
from March 21 to Sept 21
A car is accelerating when it is
going around a circular track at a steady 100 miles per hour.
The gravitational potential energy of a contracting interstellar cloud
gradually transforms into other forms of energy.
Compared to red light, blue light has higher frequency and
higher energy and shorter wavelength.
Compared to an atom as a whole, an atomic nucleus:
is very tiny but has most of the mass.
Some nitrogen atoms have seven neutrons and some have eight neutrons. These two forms of nitrogen are:
isotopes of each other.
If the Sun rises precisely due east:
it must be the day of either the spring or fall equinox.
Compared to their values on Earth, on another planet your
mass would be the same but your weight would be different.
Two stars that are in the same constellation:
may actually be very far away from each other.
Suppose you lived at a latitude of 40 degrees N. Around noon, when the Sun is high in the sky, during what time of year can you find the Sun at your zenith at noon?
never (the latitude is greater than the tilt of the Earth so the Sun can never be directly above it)
If you lived on the North Pole, after being in the dark during winter, when would you finally see the Sun rise?
on the spring equinox (March 21)
If Earth were twice as far from the Sun, the force of gravity attracting Earth to the Sun would be
one-quarter as strong.
A spectral line that appears at a wavelength of 321 nm in the laboratory appears at a wavelength of 328 nm in the spectrum of a distant object. We say that the object's spectrum is:
redshifted
If there is going to be a total lunar eclipse tonight, then you know that:
the Moon's phase is full.
The fact that we always see the same face of the Moon tells us that
the Moon's rotation period is the same as its orbital period.
What is special about locations on the Antarctic circle?
the Sun never rises above the horizon on June 21
In winter, Earth's axis points toward the star Polaris. In spring:
the axis also points toward Polaris
Compared to its angular momentum when it is farthest from the Sun, Earth's angular momentum when it is nearest to the Sun is
the same.
On the summer solstice, where would a person have to stand so that the Sun is at his/her zenith at noon?
the tropic of Cancer (23.5 degrees N- latitude) (since the latitude is the same as the Sun's tilt, the Sun is directly above the tropic of Cancer on the summer solstice)
On Dec 21, the Sun is directly above which of the following?
the tropic of Capricorn (23.5 degrees S)
A week after full moon, the Moon's phase is:
third quarter.
Suppose you lived on the Arctic Circle, and it is midnight on the summer solstice. Where is the Sun?
touching the northern horizon
Do you think Northern Hemisphere winters on Mars are warmer or colder than Southern Hemisphere winters?
warmer
If the Earth were tilted 90 degrees, summer in the Arctic would be ________ than summers in Colorado.
warmer
Beijing and Philadelphia have about the same latitude but very different longitudes. Therefore, tonight's night sky in these two places:
will look about the same.
When is the Sun highest in the sky at noon for people living 34 degrees S latitude?
winter solstice (Dec 21)
When it is summer in Australia, the season in the United States is
winter.
The North Celestial Pole is 35.0 ∘ above your northern horizon. This tells you that:
you are at latitude 35.0 ∘ N.
