Life in the Universe Old Exams
In scientific notation, 2 million is written as (a) 2 x 10^6 (b) 2,000,000 (c) 2 x 10^9 (d) 1 x 20^6 (e) 2 x 10^-9
2 x 10^6
If we discover a planet that is twice as far from the Sun as the Earth is, how far is thisnew planet from the Sun? (a) 2 AU (b) 2 parsecs (c) 2 light-years (d) 200 million km (e) 2 solar masses
2 AU
f the distance between a planet and the Sun never changes, then the planet's orbitaleccentricity must be (a) 1 (b) 0.5 (c) 10 (d) 0 (e) -1
0
Which of the following temperatures is the coldest? (a) 0 K (b) 0 C (c) 0 F
0 K
Over the course of one orbit around the Earth, how many times will the Moon spinaround on its axis? (a) 1 (b) 0 (c) 27 (d) 365 (e) 127
1
If the same side of the Earth always faced the Sun, how many times would Earth spinon its axis over the course of one orbit around the Sun? (a) 1 time (b) 0 times (c) 365 times (d) 27 times
1 time
Select the largest distance: (a) 9.5 x 10^1 meters (b) 3.3 x 10^2 kilometers (c) 1.2 x 10^8 parsecs (d) 7.8 x 10^10 AU
1.2 x 10^8 parsecs
The Moon makes one complete cycle of its phases every (a) 24 hours (b) 365 Earth-days (c) 27 Earth-days (d) 1 Earth-year
27 Earth-days
What is another way to write out 3 billion? (a) 3,000,000 (b) 3 x 10^9 (c) 1 x 10^3 (d) 9 x 10^3 (e) 9,000,000
3 x 10^9
If we discover a planet that takes 8 years to go around the Sun, what would its semi-major axis be? (Hint: think about the Earth and Kepler's 3rd law.) (a) 4 AU (b) 1 AU (c) 0.25 AU (d) 0.8 AU (e) 0.5 AU
4 AU
If we discovered a planet around the Sun with an orbital period of 8 Earth-years, whatwould its semimajor axis be? (a) 0.125 AU (b) 4 AU (c) 0.5 AU (d) 1 AU
4 AU
Of the following events, select the one that occurred first in the formation of the solarsystem. (a) Solid dust condensed at the midplane of the Sun's gaseous circumstellar disk (b) Planetesimals formed out of dust (c) A slowly rotating portion of a giant molecular cloud began to collapse under its own gravity (d) Planetesimals underwent runaway growth
A slowly rotating portion of a giant molecular cloud began to collapse under its own gravity
Which unit is best suited to measuring the distances to other planets in the solarsystem? (a) parsec (b) kilometer (c) nanometer (d) AU (e) redshift
AU
All of the following objects are in our solar system EXCEPT (a) Cepheid variables (b) the Earth's moon (c) Mars (d) Pluto (e) the Sun
Cepheid variables
In the planetary orbit shown below, where would the planet be moving slowest?
D
True or False: As elliptical galaxies age, they steadily transform into spiral galaxies.
False
True or False: If you watch the moon closely every night over the course of 27 nights,then you will see every part of its surface. (Assume it is never cloudy.)
False
True or False: Most spiral galaxies begin their lives as elliptical galaxies.
False
True or False: The Earth contains much more iron than water (which is made ofhydrogen and oxygen) because hydrogen and oxygen were much rarer elements thaniron in the Sun's circumstellar disk.
False
True or False: The distance from the Earth to the Sun would always be exactly 1 AUif the eccentricity of Earth's orbit was 1.0.
False
True or False: The gravity of all the matter in the Universe is causing the expansionrate of the universe to become slower and slower over time.
False
True or False: The photons in this spectrum were created when electrons moved from alow energy level close to the nucleus to a high one further away from the nucleus.
False
True or False: There are no other objects in the solar system that seem to have anypossibility of hosting life.
False
Which substance formed first in the Universe? (a) Hydrogen (b) Helium (c) Carbon (d) Water
Hydrogen
How will the gravitational force between two objects change if we triple the separationbetween them? (a) It will not change (b) It will become three times stronger (c) It will become nine times weaker (d) It will become nine times stronger (e) It will become three times weaker
It will become nine times weaker
How will the gravitational force between two objects change if we decrease the massof one of the objects by 50%? (a) It will not change (b) It will become twice as weak (c) It will become twice as strong (d) It will become four times stronger (e) It will become four times weaker
It will become twice as weak
Imagine the Sun's surface temperature suddenly doubled, but its size, mass, and dis-tance stayed the same. How would the Sun's appearance change to us? (a) It would appear bluer and dimmer. (b) It would appear redder and brighter. (c) It would appear redder and dimmer. (d) It would appear bluer, but its brightness would stay the same. (e) It would appear bluer and brighter.
It would appear bluer and brighter
If the Earth was suddenly moved to 0.5 AU from the Sun, how would the force ofgravity between the Sun and Earth change? (a) It would become twice as strong. (b) It would become twice as weak. (c) It would become four times as strong. (d) It would become four times as weak.
It would become four times as strong.
If the masses of both the Sun and the Earth were suddenly doubled, how would the force of gravity between the two objects change? (a) It would become twice as strong. (b) It would become four times as strong. (c) It would become twice as weak. (d) It would become four times as weak.
It would become four times as strong.
If the Earth spun slower on its axis, which of the following would happen? (Assumethere are no other changes in the solar system.) (a) Each season would last for a longer time. (b) It would take longer for the Sun to rise and set. (c) The North Star would move more each night. (d) It would take longer for the Moon to go through each of its phases. (e) We would see new parts of the Moon's surface.
It would take longer for the Sun to rise and set.
Throughout the course of a single night, every star in the sky will appear to changeits position except for Polaris, the North Star. Will this always be the case in thefuture? (a) Yes (b) No (c) This is impossible to predict.
No
Imagine there are two additional planets in our solar system: Planet X and Planet Y.The semimajor axis of Planet X's orbit is 0.5 AU, and the semimajor axis of PlanetY's orbit is 6 AU. Based on planet formation theory and this information, we expectthat (a) Planet Y is denser and more massive than Planet X (b) Planet X is denser than Y, but Y is more massive than X (c) Planet X is denser and more massive than Planet Y (d) Planet Y is denser than X, but X is more massive than Y
Planet X is denser than Y, but Y is more massive than X
Imagine we discover two planets: Planet X and Planet Y. If we look at their blackbodyspectra, we see that Planet X's peaks in the infrared at a wavelength of 1200 nanome-ters (nm), and we see that Planet Y's peaks in the infrared at a wavelength of 1500nanometers (nm). Based on this, we can conclude that (a) Planet X is hotter than Planet Y (b) Planet X is colder than Planet Y (c) Planet X is more massive than Planet Y (d) Planet X is less massive than Planet Y (e) Planet X has a higher albedo than Planet Y
Planet X is hotter than Planet Y
We experience seasons on Earth because (a) The Earth is closer to the Sun in the summer (b) The Earth's spin axis is tilted compared to its orbital plane (c) The Sun's luminosity increases in the summer and decreases in winter (d) The Moon blocks more of the Sun's light in the winter (e) The Earth has more greenhouse gases in its atmosphere in the summer
The Earth's spin axis is tilted compared to its orbital plane
Which of the following is NOT a characteristic of our solar system? (a) All of the planets' orbits lie in about the same plane. (b) Rocky planets are found closer to the Sun. (c) The most massive planets are the ones closest to the Sun. (d) Icy and gaseous planets are found further from the Sun.
The most massive planets are the ones closest to the Sun.
True or False: Compared to the planets in our own solar system, many of the planets we have found around other stars have very different masses or orbits.
True
True or False: Even though the composition of the planets is very different from thecomposition of the Sun, we believe that planets formed out of a circumstellar disk witha Sun-like composition.
True
True or False: Planets do not always move in the same direction across the nightsky.
True
True or False: We know the Universe is expanding because nearly ever galaxy we lookat is redshifted.
True
True or false: Far in the future, the Earth's north pole will not always point at thestar currently known as "the North Star".
True
True or false: There was a time when most of the matter in the universe wasn't madeof hydrogen.
True
If the photons of one type of radiation (Type A) have more energy than another type(Type B), we know that (a) Type A has a shorter wavelength than Type B (b) Type A has a longer wavelength than Type B (c) Type A travels more quickly than Type B (d) Type A has a lower frequency than Type B
Type A has a shorter wavelength than Type B
Imagine two stars (Star A and Star B) have the same identical composition, surfacetemperature, radius, and mass. In addition, both stars are the same distance fromyou. If Star A is traveling toward you at 250 km/s and Star B is traveling away fromyou at 200 km/s, which of the following is true? (a) You would observe that the blackbody spectrum of Star A peaks at a shorterwavelength than that of Star B. (b) You would observe that the blackbody spectrum of both stars peaks at the samewavelength. (c) You would observe that both stars have absorption lines at the same wave-lengths. (d) You would observe that Star A is dimmer than Star B
You would observe that the blackbody spectrum of Star A peaks at a shorterwavelength than that of Star B.
The very first stage of the formation of our solar system involves (a) dust settling at the midplane of a gas disk (b) a large gas disk that begins to heat up (c) the runaway growth of large planetesimals (d) a large gas cloud beginning to collapse under its own gravity (e) the formation of icy planetesimals beyond the snowline
a large gas cloud beginning to collapse under its own gravity
What type of galaxy do we live in? (a) a spiral galaxy (b) an elliptical galaxy (c) an irregular galaxy (d) a spherical galaxy
a spiral galaxy
A successful theory for planet formation must explain all of the following features ofour solar system EXCEPT (a) low-mass planets are close to the Sun (b) all of the planet orbits are in about the same plane (c) all of the planets have about the same composition (d) high-mass planets are far from the Sun
all of the planets have about the same composition
Imagine you discover a new blue-colored galaxy with lots of cold gas and many youngstars. Based on this information, you know that this galaxy is NOT (a) a regular spiral galaxy (b) an elliptical galaxy (c) a barred spiral galaxy (d) disk-shaped
an elliptical galaxy
The temperature of a planet's surface can be determined by studying its (a) blackbody spectrum (b) emission lines (c) albedo (d) reflectance spectrum (e) absorption lines
blackbody spectrum
If we know the true luminosity of a star as well as its brightness in the sky, it is thenvery easy to figure out its (a) distance (b) mass (c) composition (d) velocity (e) all of the above
distance
The AU is a unit that astronomers use to measure (a) temperature (b) distance (c) density (d) mass
distance
X-rays have more energetic photons than all of the following types of radiation EX-CEPT (a) gamma rays (b) visible light (c) infrared radiation (d) ultraviolet radiation (e) microwave radiation
gamma rays
This is an attractive force between any two objects that have mass: (a) strong nuclear force (b) weak nuclear force (c) electromagnetism (d) gravity
gravity
Compared to red light, blue light (a) has a longer wavelength (b) has a shorter wavelength (c) moves more slowly in a vacuum (d) has a lower frequency
has a shorter wavelength
Below is a diagram of a star that is moving in the direction indicated by the arrow.The stick figure also shows the position of an astronomer observing the star. This astronomer would see that the light from this star (a) has no doppler shift (b) has a redshift (c) has a blueshift
has no doppler shift
In the very early universe, nearly all the atoms were either hydrogen or (a) carbon (b) oxygen (c) helium (d) iron (e) sodium
helium
Which type of radiation does Earth generate the most of? (a) visible light (b) ultraviolet light (c) gamma rays (d) infrared
infrared
Of the following types of radiation, which one's photons have the lowest energy? (a) gamma rays (b) infrared light (c) visible light (d) ultraviolet light
infrared light
If a planet forms at 0.5 AU, our planet formation theory tells us that a large fractionof the planet should be made of (a) iron (b) hydrogen (c) helium (d) water ice
iron
f we increase the distance between two objects by a factor of 4, how does the strengthof their gravitational attraction change? (a) it gets 16 times stronger (b) it gets 16 times weaker (c) it gets 4 times stronger (d) it gets 4 times weaker (e) it gets 8 times stronger
it gets 16 times weaker
How does the force of gravity between two objects change if the mass of one object isdecreased by half? (a) it gets 4 times weaker (b) it gets 2 times stronger (c) it gets 4 times stronger (d) it stays the same because the force of gravity only depends on the distancebetween two objects (e) it gets 2 times weaker
it gets 2 times weaker
If the distance to a star is doubled, then how does its luminosity change? (a) it doubles (b) it quadruples (c) it decreases by a factor of 2 (d) it decreases by a factor of 4 (e) it stays the same
it stays the same
The brightness of a star in the night sky depends on (a) its luminosity and its distance (b) its magnetic field and its luminosity (c) its luminosity and its spin period (d) its distance and nothing else
its luminosity and its distance
During planet formation runaway growth causes (a) large planetesimals to grow faster than small planetesimals (b) small planetesimals to grow faster than large planetesimals (c) icy planetesimals to accrete more rocky material (d) rocky planets to capture gas envelopes (e) planets beyond the snowline to be made of ice
large planetesimals to grow faster than small planetesimals
The strength of the gravitational force between two objects depends on their (a) charge and separation distance (b) temperature and mass (c) temperature and size (d) mass and separation distance
mass and separation distance
All of the following methods are used to measure the distances to galaxies EXCEPT: (a) measuring the luminosity of Cepheid variables in galaxies (b) measuring the redshift of galaxies (c) measuring the luminosity of Type Ia Supernovae in galaxies (d) measuring the peak blackbody wavelength of galaxies
measuring the peak blackbody wavelength of galaxies
The expansion of the universe causes (a) more distant galaxies to have larger blueshifts (b) more distant galaxies to have more stars (c) more distant galaxies to rotate faster (d) more distant galaxies to have larger redshifts
more distant galaxies to have larger redshifts
The photons that make the spikes in the spectrum are related to the electrons in atoms.What are these electrons doing when the photons in this spectrum are produced? (a) moving further from the atomic nucleus (b) getting stripped from the atomic nucleus (c) moving closer to the atomic nucleus (d) attaining a more eccentric orbit around the atomic nucleus
moving closer to the atomic nucleus
If no stars rise or set throughout the course of an entire night (and it's not cloudy),you know you must be located (a) on the Earth's equator (b) in Norman, OK (c) this is actually the case anywhere on the Earth (d) on one of the Earth's poles
on one of the Earth's poles
At various points in the past, the Universe's peak blackbody wavelength has beenlocated in all parts of the electromagnetic spectrum EXCEPT (a) visible light (b) infrared (c) radio (d) microwave
radio
As the universe has expanded, its blackbody radiation has peaked in different types ofradiation. It has peaked in all of the following types EXCEPT (a) microwaves (b) radio waves (c) visible light (d) ultraviolet (e) infrared
radio waves
In order to survive, all lifeforms on Earth need all of the following EXCEPT (a) liquid water (b) nutrients (c) an energy source (d) seasonal changes in temperature
seasonal changes in temperature
Since the Big Bang, the universe's expansion rate has (a) sped up (b) stopped (c) reversed (d) slowed down
sped up
The Sun is located in a (a) elliptical galaxy (b) spiral galaxy (c) irregular galaxy (d) Cepheid variable
spiral galaxy
The largest object in our solarsystemis a (a) star (b) planet (c) asteroid (d) galaxy
star
Cepheid variables are (a) stars that only emit visible light (b) stars whose brightness varies periodically with time (c) a type of planet that forms beyond the snowline (d) stars whose composition varies periodically with time (e) a type of star that always has the same temperature
stars whose brightness varies periodically with time
if we want to figure out the composition of a star, which of the following approachesis most useful? (a) finding the peak in its blackbody spectrum (b) studying its reflectance spectrum (c) searching for nearby standard candles (d) studying its absorption lines (e) measuring its redshift
studying its absorption lines
The Sun rises and sets once every 24 hours because (a) the Earth orbits around the Sun every 24 hours (b) the Sun orbits the Earth once every 24 hours (c) the Moon eclipses the Sun once every 24 hours (d) the Earth spins on its axis once every 24 hours
the Earth spins on its axis once every 24 hours
The temperature in Oklahoma is warmer in July than in January. This is because (a) the Earth is significantly closer to the Sun in July than in January. (b) it is cloudier in January than in July. (c) the Sun's surface temperature oscillates every year. (d) the Earth's spin axis is tilted by 23 degrees relative to its orbital plane
the Earth's spin axis is tilted by 23 degrees relative to its orbital plane
The positions in the sky of all of the following objects change throughout the courseof a day/night cycle EXCEPT (a) the North Star (b) the Sun (c) the Moon (d) Mars (e) Proxima Centauri (the closest star to the solar system)
the North Star
All of the planets in our solar system orbit (a) each other (b) the Earth (c) the Sun (d) the Moon
the Sun
Every planet in our solar system orbits around (a) the Moon (b) the Earth (c) the Sun (d) Mars
the Sun
Which of the following objects produce their own visible light? (a) Mars (b) Mercury (c) the Moon (d) the Sun (e) Pluto
the Sun
Planet X reflects half of the light that hits it, but Planet Y reflects all of the light thathits it. Based on this, we know that (a) the albedo of Planet X is twice as small as Planet Y's (b) the albedo of Planet Y is twice as large as Planet X's (c) Planet X has a thicker atmosphere than Planet Y's (d) Planet X must be made of more rock than Planet Y (e) Planet Y must be more massive than Planet X
the albedo of Planet Y is twice as large as Planet X's
If we change the wavelength of light, all of the following will also change EXCEPT (a) the frequency of the light (b) the speed the light travels through a vacuum (c) the photon energy of the light(d) the color of the light (assuming it's visible) (e) none of the above
the speed the light travels through a vacuum
Measuring the peak wavelength of an object's blackbody spectrum will tell us (a) the composition of the object (b) the size of the object (c) the age of the object (d) the surface temperature of the object
the surface temperature of the object
Which of the following is NOT a technique to estimate the distance to the very furthestgalaxies? (a) using Cepheid variables to measure their distance (b) measuring their redshift and then using Hubble's Law (c) using Type Ia supernovae to measure their distance
using Cepheid variables to measure their distance