Emptiness of Universe





the night sky is relatively dark because

A the Earth's atmosphere obscures most of the light

B the universe is mostly empty

C the universe is expanding

D the universe is very large and old



the space between "objects" in the universe, compared to the objects themselves, is

A densely filled with matter

B bright with light from all the objects

C loosely occupied with matter and light

D totally empty



a basic observation of the nature of the universe is that

A matter is uniformly distributed through space

B matter and antimatter exist in equal amounts

C matter is distributed in clumps with large empty space between clumps

D light is more important than matter in describing the state of the universe



matter in the universe, whether considering astronomical objects or individual atoms, is

A very tightly packed

B mostly empty space

C filled to capacity

D totally empty



the universe, and all the objects in it, is

A very tightly packed with matter

B mostly empty space

C permeated with an unknown substance for light to travel in

D held together by the nuclear force



a single phrase which best describes the universe is

A brightly illuminated by stars

B mostly empty space with scattered clumps of matter

C filled with so many different kinds of objects as to be beyond our comprehension

D filled with randomly moving stars with no apparent pattern



from an overall point of view the universe is

A uniformly filled with various objects

B rather clumpy with large empty regions between major objects

C unsuited to serious scientific study because of its disorder

D densely filled with little empty space



the space between clumps in the universe is

A densely filled with individual atoms

B mostly empty space with vast distances between clumps compared to the size of the clumps

C mostly empty space but with the clumps fairly close together compared to t he size of the clumps

D totally empty space



the observed universe is

A very tightly filled with stars and galaxies

B filled with relatively dense gas in which the stars and galaxies are embedded

C random stars positioned throughout the volume, not grouped together

D mostly empty space



which of the following observations of the nature of the universe can be made without using any scientific equipment

A most galaxies are moving away from us

B half of the universe is anti-matter and half is ordinary matter

C luminous matter in the universe is not evenly distributed, but occurs in clumps

D a background radiation is left from the flash at the big bang



the universe can be considered to be

A densely packed with matter

B mostly empty space

C composed of only a few objects

D a mirror image of the solar system



which of the following statements best describes our universe

A it is uniformly filled with matter

B it is densely filled with matter

C it is mostly empty space

D none of the above

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Clumps of Matter





an object is defined to be any collection of things in which the individual pieces are

A close together compared to their sizes

B held together be external forces

C small compared to other objects

D close together compared to the distances to other objects



one brief description of a star is

A a small point of light seen only at night

B a radiant body at least 3 million times as massive as the Earth

C a bright object with a five-pointed shape

D a body which shines from its own internal source of energy



the number of galaxies in the observable universe is

A greater than the number of stars in our galaxy

B millions

C thousands

D a few hundred



a galaxy is

A any physical group of stars

B any physical group of stars with more than 1 million members

C an independent group of stars, widely separated from its neighbors

D a group of stars with at least a billion members



in the hierarchy of clumps, the first to begin to form are

A galaxies

B stars

C clusters of galaxies

D clusters of stars



clusters of stars are frequently broken up by

A violent explosions within the cluster

B random motion of a cloud of gas

C evaporation as stars randomly leave the group

D the formation of galaxies



the condensations which form in the expanding universe are held together by

A pressure

B gravity

C density

D light



a star is

A any glowing body

B any large, gaseous body

C an object which shines from a stable source of energy

D any bright point of light in the sky



about how many stars make up the milky way galaxy?

A between 50 and 100.

B between 500 and 1000.

C between 1,000,000 and 100,000,000.

D about a billion.

E a few hundred billion.



why are clouds of gas not considered astronomical clumps

A they do not emit their own light

B they are not held together by their own force of gravity

C they are too large

D they are too young



a galaxy is

A a large cloud of gas

B an exploding star

C the object from which all other objects in the universe were formed

D a collection of a large number of stars



the largest identifiable "structure" in the universe is a

A galaxy

B star

C quasar

D cluster of galaxies



an average size for a galaxy is

A one light year

B one astronomical unit

C 100,000 light years

D one billion light years



a cluster of galaxies is a clump because

A nothing is larger

B it is widely separated from other clumps

C it is very compact

D it is very bright



object formation in the universe begins

A with the smallest objects first

B in large clouds of gas

C as gas collecting around a dense object

D with a violent explosion



a typical galaxy will

A be mostly composed of clouds of gas

B contain a million stars

C be mostly empty space

D turn into a quasar



the number of star clusters in a typical galaxy is about

A a few thousand

B a few million

C a few billion



compared to their sizes, which type of object is closest together on the average

A stars

B planets

C galaxies

D impossible to tell



an isolated group of billions of stars is a

A cluster of stars

B cluster of galaxies

C galaxy

D black hole



an independent group of a few billion stars is a

A solar system

B star cluster

C supercluster of galaxies

D galaxy



the largest clumps of matter in the universe are

A galaxies

B atoms

C stars

D planets



most celestial objects visible to the naked eye in the night time sky are

A clouds of gas

B galaxies

C planets

D stars just like our sun



a typical galaxy contains roughly

A one thousand stars

B one hundred thousand stars

C 100 billion stars

D no stars at all



which of the following objects is the most common throughout the universe

A galaxies

B clusters of galaxies

C stars

D supernovae



a planet is an object which

A occurs only in our solar system

B is too faint to see

C orbits a star

D does not generate its own energy from nuclear reactions



a star is

A any bright point of light in the sky

B any celestial object that glows

C any celestial object composed of gases

D an object which produces energy from a stable source



a planet is defined as

A a small (in comparison to the sun) rocky object

B any object which moves in the sky

C an object which does not produce its own light

D any object within a billion miles of the sun



a group of a few million stars, widely separated from other objects, is a

A cluster of stars

B galaxy

C solar system

D cluster of galaxies



the solar system contains

A everything in the universe

B the sun and everything whose motion is controlled by the sun

C all the stars in our galaxy

D the sun and several neighboring stars



which of the following is the largest?

A the sun

B a galaxy

C the largest star

D the solar system

E the Earth-moon system



a star is any object which

A shines with its own stable energy source

B appears as a point in a telescope

C is visible in the night sky

D has nuclear reactions



galaxies are

A groups of billions of stars.

B invisible with any telescopes we now have.

C dust clouds in space.

D typically 10 to 100 times larger than the solar system.

E more than one of the above.



a planet is defined to be

A any solid object in space

B an object that does not shine

C any object that directly orbits a star

D one of the nine objects in our solar system that orbits the sun



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General Definitions





when viewing celestial events, past events are always seen because

A data analysis is time consuming

B we must wait for the Earth to get to the proper place in its orbit

C the speed of light is finite

D the universe is very old



the sun is one of about how many stars in the milky ways galaxy?

A 100 million

B one billion

C 100 billion

D one trillion



past celestial events can be studied

A when observing distant objects

B only through geologic records on the Earth

C only if the hypothetical time-machine is discovered

D not at all



a light year is

A the characteristic size of light

B the distance the Earth travels around the sun in one year

C the distance light travels in one year

D the time it takes light to travel once around the Earth's orbit



constellations are

A apparent patterns or designs of stars in the sky

B realistic physical arrangements of stars in the sky

C specific arrangements of stars used to map the sky

D two of the above



a very distant object is viewed

A as it exists today

B as it existed many years ago

C as a distorted image of its appearance long ago

D as it existed at the beginning of the universe



a light year is

A the distance traveled by light in one year

B the distance the Earth moves in one year

C the time it takes light to go once around the Earth's orbit

D the time it takes light to travel one year



a light year is

A the distance between the Earth and the sun

B the length of time it takes light to reach the Earth from the sun

C the distance light travels in one year

D the size of the universe



if we observe an explosion in a galaxy which is one million light years from us, the explosion

A is occurring now

B will occur in one million years

C occurred one million years ago

D occurred at some time in the past which depends on how fast the galaxy is moving



the astronomical unit is defined as

A the time between astronomical observations

B the mean distance between the Earth and the sun

C a unit for measuring the amount of work astronomers do

D no choice



past events can be studied

A only through geologic records

B by observing distant celestial objects

C only as recalled by the people

D not at all



a light year is

A a unit of time

B a unit of length

C a unit of brightness

D an angular unit



a light year is

A the length of time it would take the Earth to go around the sun at the speed of light

B the distance light travels in one year

C the distance around the Earth's orbit

D the distance across our galaxy



the light year is

A the length of time it takes light to travel to the nearest star

B the distance a beam of light travels in a year

C the number of seconds in a year

D the size of a typical galaxy



the light year is

A a unit of time

B a unit of length

C related to the way in which the Earth orbits

D a unit used to distinguish different colors



a light year is

A the distance light travels in one year

B the time it takes the Earth to go around its orbit once

C the distance from the sun to the Earth

D the distance to the nearest star



if the nearest star is 4.2 light-years away then

A the light we see left the star 4.2 years ago.

B the star is 4.2 million au away.

C the star must have formed 4.2 billion years ago.

D all of these.



the speed of light is about

A 600 miles per hour

B 186,000 miles per second

C 240,000 miles per second

D 93,000,000 miles per second



a light year is equal to

A 6*10**12 miles

B 6*10**-9 inches

C 3*10**7 seconds

D 1.86*10**5 miles/sec.



a galaxy at 1 million light years is seen to explode. we may definitely say that

A the galaxy has just exploded

B the galaxy exploded one million years ago

C the galaxy will explode in one million years

D nothing happened except that the photons were modified while traveling to us



the sun is an example of a

A planet.

B star.

C protostar.

D asteroid.



the milky way consists of

A one star, nine major planets, and at least 35 moons

B about 400 billion stars (and their planets if they have any)

C about twenty nearby galaxies including our own

D a tiny fraction of all the stars whose distances can be measured using the parallax effect



a light year is

A one solar year

B one daytime year

C the amount of light generated by the sun in a year

D the distance light travels in a year



an explosion is observed on a star which is twenty light years away. if the explosion is observed in 1989, it occurred in

A 1989

B 2009

C 1969

D can't tell without additional information



a light year is a measure of

A distance

B arc length along an orbit

C expansion rate of the universe

D time



the solar system

A consists of one star, nine major planets, and at least 35 moons

B contains about 400 billions stars and is so wide that light takes many thousands of years to cross it

C includes all the objects we can see in space

D contains all objects to which we can measure distances using radar



1 light year is

A the distance between Earth and sun

B the time taken for Earth to orbit the sun once

C a time interval, using the speed of light as a reference

D the distance that light travels in 1 year



the average distance from the Earth to the sun is

A 1 au.

B 1 ly.

C 1 million km.

D none of these.



one astronomical unit is

A the distance across the solar system.

B the time required for light to travel all the way around the Earth's orbit.

C the average distance from Earth to sun.

D 93 million seconds.

E the distance Earth travels around the sun in one year.



a light year is equal to

A 186,000 miles/sec

B 3*10**7 seconds

C 6*10**12 miles

D 4*10**-9 inches



in scientific notation, the number 400 million is written as

A 4*10**6

B 4*10**8

C 4**10

D 4*10**-8



the number 30 million can be written as

A 3*10**6

B 3**6

C 30**6

D 3*10**7



in scientific notation the number 6 billion is written as

A 6*10**6

B 6*10**9

C 6**10

D 6*10**-8



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Scale of Universe





in ordinary solid matter, the atoms are

A very widely separated

B not moving at all

C densely packed

D held together by the force of gravity



a typical distance between star systems in the disk of the milky way is

A a few light years

B a trillion miles

C a billion miles

D a million miles



in a model of an atom in which the nucleus is a softball, the atom would occupy an area roughly equal to

A a typical desk

B the WSU campus

C Wichita

D the United States



in a scale model of the solar system in which the sun is the size of a softball, the solar system would be about

A 1000 miles across

B one mile across

C fifty feet across

D one foot across



a scale model of the solar system in which the sun is the size of a softball shows that

A the Earth is very close to the sun compared to its size

B the solar system is mostly empty space

C the solar system is very irregular

D the nearest star is just barely outside the solar system



in a scale model of the universe in which the sun is a softball, the solar system would occupy

A the entire united states

B the WSU campus

C this classroom

D the top of an average desk



approximately 1 light year from the sun

A is totally empty space

B lie the trojan comets

C lie the lagrangian points

D lies the Oort cloud



in a scale model in which the sun is the size of a softball, how far away would the nearest star be

A 100 yards

B 10 miles

C 2,000 miles

D at the sun itself



in a scale model in which the sun is the size of a softball, the solar system would occupy an area equal to

A this classroom

B the WSU campus

C the state of Kansas

D the north American continent



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Forces





the electric force does not dominate the everyday world because

A it is too weak

B it acts only over short distances

C positive charges cancel the effects of negative charges

D it is a fictional force



the fundamental force with the shortest range is

A gravity

B magnetic

C electrical

D nuclear



of the four physical forces at work in the universe, gravitation, electromagnetic, strong nuclear and weak nuclear forces, which two of the are very short-ranged

A strong and weak nuclear forces

B strong nuclear and electromagnetic forces

C gravitation and electromagnetic forces

D electromagnetic and weak nuclear forces



electricity does not dominate our motion the way gravity does because

A it is too weak to be significant

B it only acts over short distances

C it only acts over huge distances

D the effects of positive and negative charges cancel each other



gravity is

A sometimes a repulsive force and sometimes an attractive force

B always a repulsive force

C always an attractive force

D none of these



the electric force is not important over large distances in the universe because

A it is a short-range force and dies out quickly

B it is responsible for binding atoms together into chemical elements

C there are two kinds of electrical charge--positive and negative

D the electrical force is the weakest of the three known forces of nature



of the four forces in nature, the one that is inherently the weakest is

A strong nuclear

B weak nuclear

C electromagnetic

D gravitational



the force which holds us on the surface of the Earth is

A nuclear

B electrical

C centrifugal

D gravity



for the fundamental forces it can be said that the longer the range of the force, the

A stronger the force

B the weaker the force

C faster acting the force

D longer acting the force.



as a general rule, the weaker the force the

A shorter the range

B longer the range

C strength is not related to the range

D the range of all fundamental forces is the same



the strongest of the fundamental forces is

A gravitation

B electric

C magnetic

D nuclear



since the "weak" force is weaker than the nuclear force, its range is

A larger

B smaller

C the same

D unknown



the physical force which controls the structure of the nucleus and binds together protons and neutrons is the

A gravitational force

B strong nuclear force

C weak nuclear force

D electromagnetic force



which of the following is not a "fundamental" force of nature

A the force of gravity holding you to the Earth

B the nuclear force acting to hold the particles in a nucleus together

C the repulsive force of electricity acting between two electrons

D the pull of centrifugal force which tries to pull you out of the car as you turn a corner



gravity is an attractive force which affects

A only things with mass, such as protons and electrons

B only things with electric charge, such as protons and electrons

C everything in the universe except photons and neutrinos

D everything, period



the weakest fundamental force is the

A weak nuclear

B electric

C gravitational

D strong nuclear



the only fundamental force that is significant for distances on the order of the size of the universe is

A gravity

B magnetism

C nuclear

D weak



the force that holds a molecule together is

A nuclear

B electrical

C centrifugal

D gravitational



in an equilibrium situation

A nothing is happening

B two counteracting processes cancel out

C any small change will immediately destroy the equilibrium

D no change is ever possible



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Philosophy





Olbers' paradox assumes that the universe

A is completely filled with light

B has always been the way it is now

C is infinitely old and infinitely large

D is finite in at least one aspect



which of the following could help to explain Olbers' paradox

A the leaky photon theory

B expansion of the universe

C finite age of the universe

D all of these



if the light of a star was visible in every single direction, then

A Olbers' paradox would be wrong

B the sky would by exceedingly bright

C the age of the universe would be finite

D stars would have to be very close to each other



Olbers' paradox is

A correct as stated

B confirmed by observation

C inconsistent with a dark night sky

D correct only in the early universe



Olbers' paradox assumes

A a finite universe with an infinite amount of matter

B an infinite universe with an infinite amount on matter

C an infinite universe with a finite amount of matter

D a finite universe with a finite amount of matter



Olbers' paradox assumes that

A the universe is infinite

B the universe is finite

C the universe is very old

D the universe is static



which of these are important aspects of a scientific model?

A it is testable by observations.

B it is aesthetically pleasing by the standards of the time.

C it uses physical ideas to explain phenomena.

D it contains geometrical elements.

E all of the above.



an object in the universe is said to be real only when

A its properties can be predicted

B phenomena associated with it, such as light waves, can be detected

C it can be explained

D it can be directly experienced by man



which of the following is not a criterion for a good scientific theory?

A a theory should be aesthetically pleasing.

B a theory should be agreed upon by all knowledgeable scientists.

C it should be possible to prove the theory wrong.

D a theory should fit present data.

E none of the above is correct. all are criteria for a good theory.



which of the following is not generally considered a step in the "scientific method"?

A gathering of observations

B construction of a theory to explain the observations

C testing of the theory by further experiment

D publishing of the results in a reputable scientific journal



a basic assumption of all astronomy is that

A all objects in the universe are detectable

B Einstein's theory of relativity is correct

C Hubble's law applies to all objects

D all laws of nature apply uniformly throughout the universe



in order for a prediction to lend weight to a theory it must first be observed to be correct

A after the prediction has been made

B before the prediction is made

C by the same person who made the prediction

D at non-relativistic speeds



a basic assumption of all science is that

A all laws of nature are relative

B the laws of nature are unique because of the location of the Earth

C the idea of a law of nature has no meaning

D all laws of nature as discovered on the Earth apply throughout the universe







the assumptions of a new theory must be

A derivable from previous theories

B expressible in a mathematical formula

C consistent with previous observations

D predictions for future observations



in what ways can observations affect scientific models?

A they can confirm or refute predictions of models.

B they can directly observe elements of the model.

C they have very little effect on models today.

D they have no connection with the development of models.



which of the following is not a part of the modern science of astronomy?

A the study of the evolution of stars.

B the study of the effects of stars and planets on the lives of people.

C the study of the characteristics of planets.

D the study of the evolution of the universe.



a basic assumption underlying all astronomy is

A the uniformity of nature

B that the universe is ageless

C only stars can emit light

D quasars obey Hubble's law



in scientific circles, the word theory is understood to mean

A an opinion held by a scientist who is famous

B an elaborate piece of speculation

C a guess which seems reasonable to many scientists

D a satisfying explanation that exposes connections between seemingly unconnected facts



before a model is accepted one must

A prove its assumptions

B derive it from existing laws of nature

C confirm its predictions

D have it approved by leading scientists



most astronomical observations

A can be tested by direct experimentation

B can be analyzed only by analogy to events observed in the laboratory

C can only rarely be understood in terms of events observed in the laboratory

D are beyond our ability to understand regardless of how much we study events in the laboratory



scientific models are

A approximate explanations of events

B exact laws of nature

C only very rarely accurate enough to be useful, even for simple events

D usually only loosely related to events in the real world



a scientific model is

A a collection of well documented facts

B a proposed explanation of an observed quantity or effect

C an absolutely true natural law

D a prediction of future events not based on past observations



science is a model building subject because

A scientists must build models to convince congress to fund their work

B models give us something to decorate our labs

C most of the things we study cannot be directly observed

D natural events are too complicated and erratic to understand directly

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