Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
48 Cards in this Set
- Front
- Back
|
If you were to specify your address int he universe, listing your membership from the smalels t to larges physical structures, it would be
|
Earth, Solar System, Milky Way, Local Group, Virgo Supercluster, the universe
|
|
|
Which of the followin is FALSE?
|
A scientific theory is an undisputed fact
|
|
|
No matter where you are on Earth, stars appear to rotate around a point called the
|
celestial pole
|
|
|
Assume you are observing the night sky from a typical city in the US at a latitude of +40 degrees. Use the figure to determine which constellation of the zodiac would be nearest to due South at 6 pm in Septemeber
|
Scorpius
|
|
|
If you went out tonight and looked at the sky at midnight, at what time would you have to observe 6 months from now in order to find stars in exactly the same postition in the sky? Assume that you could see the stars at any time, day or night.
|
Noon
|
|
|
Which of the following was NOT an idea shared by ancient Greek philosophers?
|
Stellar parallax can be measured
|
|
|
Which of the following was not one of Galileo's discoveries?
|
Stellar parallax
|
|
|
When the geocentric model of the solar system did not match the observed positions of the planets,
|
Ptolemy added epicycles to the geocentric model to try to match the observed data
|
|
|
The Ptolemaic model had all of the following traits except one. Which trait was lacking in Ptolemy's model of the universe?
|
A simplistic elegance
|
|
|
Which of the following is not one of Kepler's Laws?
|
The force of gravity is inversely proportional to the square of the distance
|
|
|
Which of the following is not one of Newton's laws?
|
No object can travel faster than the speed of light
|
|
|
If the distance between the Earth and Sun was cut to a third, the gravitational force between these two objects would
|
Increase by a factor of 9
|
|
|
If the wavelength of a beam of light were to double, how would that affect its frequency?
|
The frequency would be two times smaller
|
|
|
How do the wavelength and frequency of red light compare to the wavelength and frequency of blue light?
|
Red light has longer wavelength and lower frequency than those of blue light
|
|
|
Which of the following lists different types of electromagnetic radiation in order of increasing wavelength?
|
Gamma rays, ultraviolet, visible, infrared, radio waves
|
|
|
As wavelength increases, the energy of a photon.....and its frequency....
|
Decreases;decreases
|
|
|
Which of the following is not one of Kirchoff's laws?
|
The flux of an object goes as the temperature to the fourth power
|
|
|
As a blackbody becomes hotter, it also becomes....and....
|
More luminous, bluer
|
|
|
The Stefan-Boltzmann law states taht F = T4. If a star emits 10 to the 23 ergs/sec/m, how much flux will a star with twice the temperature emit?
|
Sixteen times as much
|
|
|
One reason to prefer a reflecting over a refracting telescope is its..
|
All of the above are valid reasons
|
|
|
The angular resolution of a ground-based telescope is usually set by
|
Atmospheric seeing
|
|
|
Cameras that use adaptive optics provide higher spatial resolution images primarily becase
|
Deformable mirrors are used to correct the blurring due to Earth's atmosphere
|
|
|
Stars A and B appear equally bright, but star A is twice as far away from us as star B. Which of the following is true?
|
Star A is four times as luminous as star B
|
|
|
Star A is twice as hot as star B. If star A is four times brighter than star B then
|
Star B is two times closer than star A
|
|
|
Which of the follwoing properly describes changes in stellar properites as you move along the man sequence on an HR diagram from the lower right to upper left?
|
Stars get larger, hotter, more massive, and more lumious
|
|
|
What fraction of stars is on the main sequence and which one property ultimately determines all the other properties of a main sequence star?
|
90%, mass
|
|
|
Why is hydrogen burning the main energy source for main-sequence stars?
|
All of the above are valid reasons
|
|
|
Hydrostatic equilibrium is a balance between
|
Pressure and gravity
|
|
|
I flew to the Sun and made some measurements of its atmosphere at different altitudes. I measured 3 temperatures of 1,000,000 K, 6,000 K, and 20,000 K. In which layers of the atmosphere did I make each of these 3 measurements, in order?
|
The corona, the photosphere, and the chromosphere
|
|
|
Which of the following properly describes the interior or the Sun?
|
The inner 70% transfers energy via radiation; convection dominates energy transfer in the outer 30%
|
|
|
Which of the following is not a property of the interstellar medium?
|
Dust fills most of the galaxy glowing in optical wavelenths
|
|
|
Which of the followin is not a manifestation of solar magnetic activity?
|
Differential rotation
|
|
|
A young protostar is....than the Sun even though its surface temperature is....
|
more luminous; cooler
|
|
|
A protostar's evolutionary Hayashi track on teh HR diagram traces out
|
A decrease in size and luminosity with a slight increase in temperature
|
|
|
If you wanted to study regions where star formation is currently happening you could us
|
All of the above
|
|
|
The entire process of star fomation is really just an evolving balance between
|
pressure and gravity
|
|
|
A main sequence star converts mass (M) into energy. It's luminosity (L) gives how much energy is given off per unit time. Therefore, the lifetime of a main sequence star should roughly go as
|
M/L
|
|
|
When a G2 star leaves the main sequence,
|
Its luminosity and radius increase but its surface temperature decreases
|
|
|
A low-mass red giant star's energy comes from
|
hydrogen burning to helium in a shell surrounding its core
|
|
|
Which of the following gives the correct evolutionary sequence for a low mass star?
|
Main sequence, red giant, horizontal branch, asymptotic giant branch, planetary nebula, white dwarf
|
|
|
When helium fusion begins in the core of red giant, the situation quickly gets out of control because electron-degeneracy pressure does not respond to changes in
|
temperature
|
|
|
If you measure the average brightness and pulsation period of a Cepheid variable star, you can also determine its
|
distance
|
|
|
An iron core cannot support a massive main-sequence star because
|
Iron cannot fuse with other nuclei to produce energy
|
|
|
A binary system always has one star evolve before the other. When the second star evolves it will begin to dump mass onto the star that has already evolved. Which is not a possible outcome?
|
Type II supernova
|
|
|
Which of the following is a consequence of Einstein's special theory of relativity?
|
Moving clocks run quicker
|
|
|
Essentially all the elements heavier than carbon in the universe were formed
|
in cores of massive stars and their supernovae
|
|
|
The Cosmological Principle states that
|
All of the above are correct
|
|
|
Astronomers have known that galaxies are separate entities outside of our own for roughly the last
|
90 years
|
