Due Date: Apr. 21, 2008
Instructions: Print and complete the following homework assignment. Make sure you write your name on the paper.
Name: ________________________________________
Circle whether each statement is True or False (1 pt each).
True False : The observable universe is probably only a tiny portion of the entire universe.
True False : A constellation is a region of the sky with well-defined borders.
True False : The fact that the Earth is in an elliptic orbit about the Sun is the major reason for the seasons.
True False : Most lunar eclipses are total lunar eclipses.
True False : Galileo's key discovery was that planetary orbits are elliptical.
True False : Occam's razor says that one should prefer the simpler of two models that agree equally well with observations.
True False : A theory is a hypothesis that has been proven to be true.
True False : Acceleration is the rate at which velocity changes.
True False : If two objects are going at the same speed, the one with the greater mass will have the greater momentum.
True False : Conservation of energy states that the total momentum of interacting objects cannot change as long as no external force is acting on them..
True False : Tides are caused by the Earth being stretched from its center both towards, and away from, the Moon.
True False : Emission and absorption spectra of a given element will show the same spectral lines.
True False : Wavelength and frequency are the same thing.
True False : Light collecting area and angular resolution are more important than magnification for a telescope.
True False : The Sun's interior consists of a convection zone, radiation zone, and the core.
True False : The Sun is slowly getting brighter.
True False : We can tell that there are large magnetic fields in sunspots by looking at the Stark shift of absorption lines in spectra of sunspot regions.
True False : The H-R diagram plots luminosity versus temperature.
True False : Stars spend most of their lifetimes as giants or supergiants.
True False : High-mass stars form more slowly than low-mass stars.
True False : In a newly formed star cluster, stars with low masses greatly outnumber stars with high masses.
True False : High-mass main-sequence stars are more luminous than low-mass main-sequence stars.
True False : As stars leave the main sequence (i.e., as they start to die) they become larger.
True False : All elements heavier than helium were formed after the Big Bang.
True False : Iron fusion can produce energy.
True False : The presence of a close companion star can affect the life of a star.
True False : A white dwarf can produce a supernova.
True False : The radius of a black hole is the distance from the center of the black hole to the event horizon.
True False : The Milky Way is an example of a lenticular spiral galaxy.
True False : All stars in the Milky Way follow roughly similar orbits about the galactic center.
True False : It is believed that there is a large black hole at the center of the Milky Way.
True False : All of the material used to form a generation of stars will eventually be recycled to form later generations of stars.
True False : The Milky Way's spiral arms rotate about the galactic center in the same way as disk stars.
True False : The Milky Way probably formed from multiple protogalactic clouds.
True False : The collision of two spiral galaxies can form an elliptical galaxy.
True False : The type of galaxy formed by a protogalactic cloud might be determined by the clouds chemical composition.
True False : Starburst galaxies represent a stage of evolution that many galaxies may have through at least once.
True False : WIMPs and GEEKs are two possible candidates for dark matter.
True False : The rotation curve for the Milky Way suggests the existence of dark matter.
True False : The orbits of galaxies in clusters suggests the existence of dark matter.
True False : The presence of black holes at the center of most galaxies suggests the existence of dark matter.
True False : It is believed that the Universe's rate of expansion has been constant.
Fill in the blanks (2 pts each).
LHC stands for _____________ _____________ _________________.
The closest star (other than the Sun) is approximately _________________ light years away.
The altitude of the celestial pole in your sky is equal to your __________________ .
Earth's equator is tilted approximately ______________ degrees from the ecliptic.
A _______________ model places the Earth at the center of the universe.
Modern science seeks explanations for observed phenomena that rely solely on _______________ causes.
The standard unit of force is the _________________.
Newton's first law states that an object moves at constant velocity if there is no net _____________ acting upon it.
Every mass attracts every other mass through the force called ______________.
_______________ _______________ have longer wavelengths than any other type of electromagnetic wave.
Name the closest star to the Earth. ___________________________
_____________________ is a star's most fundamental property.
The total power output of a star is referred to as the star's __________________ .
A star's entire life is a battle between _________________ and pressure.
Apparent brightness follows an inverse _______________ law with respect to distance.
Stars form from __________________ clouds.
The final stage in the birth of a star is ___________________ fusion.
All pulsars are ___________________ stars.
The maximum mass of a star is approximately _______________ MSun.
The three main types of galaxies are spiral, elliptical, and ________________________.
The oldest stars in the Milky Way occur in _______________ clusters.
The distance to most galaxies is measured by using _________________________ candles.
________________ law states that more distant galaxies move away from us faster.
The reciprocal of _______________ constant tells us the age of the Universe.
All quasars are believed to be supermassive ______________ __________________.
Calculate (attach a separate sheet for the answers in this section) each of the following. Show all of your work. Note that you must explicitly write the correct units for each problem. (20 pts each).
What is the distance of a galaxy that is moving away from us at a velocity of 3 x 104 m s-1?
What is the redshift of a galaxy that is moving away from us at a velocity of 3 x 104 m s-1?
What is the radius of a four million solar mass black hole?
Find the apparent brightness of a type Ia supernova that is 2 billion light years away.