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77 Cards in this Set
- Front
- Back
During one part of the nitrogen cycle, nitrogen is removed from the air mainly by nitrogen-fixing
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bacteria
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Atmospheric pressure measured at sea level is
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1.03kg/cm squared
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A barometer measures
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atmospheric pressure
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Almost all of the water and carbon dioxide in the atmosphere is in the
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troposphere
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Readio stations can increase the distances they reach by bouncing radio waves off the
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ionosphere
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Around Los Angeles, frequent temperature inversions are the result of coll, polluted air abeing trapped by
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mountains
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Almost all of the energy reaching the earth from the sun is in the form of
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electromagnetic waves
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Raindrops may separate sunlight into a range of colors, thereby causing
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a rainbow
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The process in which the atmosphere traps warming solar rays at the earth's surface is called the
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greenhouse effect
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Heat can be transferred within the atmosphere in three ways: radiation, conduction, and
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convection
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A vertical looping pattern of air flow is known as
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convection cell
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A gentle wind covering less than 100 km is called
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a breeze
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The prcess by which ice changes directly into water vapor is referred to as
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sublimation
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Relative humidity is always expressed
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as a percentage
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TO express the actual amount of moisture in the air, meteorologists use
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specific humidity
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When air temperature drops, its capacity for holding water is
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lower
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The tiny droplets that result when air is cooled by contact with a cold surface are called
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dew
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Changes in temperature that result soley from the expansion or compression of air are called
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adiabatic
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Clouds form when the water vapor in air condenses as
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the air is cooled
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Low sheetlike clouds are called
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stratus clouds
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The term nimbo or minbus added to the name of any form of cloud means
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rain
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The fog that results from the nightly cooling of the earth is called
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radiation fog
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Rain that freezes when it strikes the ground produces
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glaze ice
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Clouds in which the water droplets reamin liquid below 0 degrees Celsius are said to be
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supercooled
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In one method of cloud seeding, silver-iodide crystals are used as
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freezing nuclei
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A wide-mouth funnel and a cylindrical container are used in making an instrument called a
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rain gauge
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In the majority of stars, the most common element is
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hydrogen
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The color of the hottest stars is
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blue
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Stars appear to move in curcular paths around the Polaris because
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the earth rotates on its axis
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The change in position of a newarby star compared with the position of a faraway start is called
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red shift
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The brightest stars have apparent magnitudes that are
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negative numbers
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THe absolute magnitude of a star is
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the true brightness of the star
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A protostar becomes a star when it begins to
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generate energy
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A main-sequence star genrate energy by fusing
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hydrogen into helium
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A dying star can shed some of its gases as a
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supernova
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Black holes are difficult to locate because they
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do not give off light
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A pattern of stars is called a
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constellation
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Stars appear in fixed locations in the sky because they
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are so far from the earth
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The basic types of galaxies are
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spral, elliptical, and irregular
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Quasar formation is associated with
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the big bang
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According to Einstein's theory of relativity, in the formula E = mc squared, the c stands for
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the speed of light
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A nuclear reaction in which two two atomic nuclei combine is called
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fusion
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THe portion of the sun in which energy moves from atom to atom in the form of waves is called the
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radiative zone
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The portion of the sun normally visilbe from the earth is the
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photosphere
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The sunspot cycle lasts
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11 years
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Sudden outward eruptions of electrixally charged atomic particles from the sun are called
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solar flares
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Gusts of solar wind can cuase
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magnetic storms
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Northern lights and southern lights are other names for
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auroras
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The hypothesis that the sun and the p lanets developed out of the same cloud of gas and dust is called the
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nebular theory
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The small bodies of matter that filled the solar nebula are called
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protoplanets
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Compared with the size of the present day planets, the protoplants were
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larger
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The first atmosphere of the earth had a high percentage of
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helium
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In the process of photosynthesis, cyanobacteria and green plants give off
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oxygen
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Water vapor began to condense into oceans about
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3 billion- 3.5 billion years ago
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Ptolemy modified Aristotle's model of the universe to include
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retrograde motion
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Copernicus's model of the solar system differed from Prolemy's because it was
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heliocentric
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Kepler's first law states that each planet orbits the sun in a path called
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an ellipse
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The weak magnetic field around Mercury suggests
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a core of molten iron
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The planet that rotates in a direction that is opposite the direction of the other planets is
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Venus
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The tilt of the axis of Mars is nearly the same as that of
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the earth
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The most distinctive feature of Jupiter is its
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Great Red Spot
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All of the outer planets in the solar system are large except
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Pluto
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The asteroid belt exists in a region between the orbits of
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Mars and Jupiter
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The compostion of asteroids suggests that they are
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fragments of planetesimals
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Meteorites can provide information about
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the composition of the solar nebula before the earth and its moon formed
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Dark areas on the moon that are smooth and reflect little light are called
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maria
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Most of the information astronomers have gathered about the interoir of the moon has come from
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seismographs
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Soon after the moon formed, it was covered with
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molten rock
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In the most recent stage in the development of the moon,
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the number of meteorites hitting the moon decreased
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The moon is closest to the earth at
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perigee
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During each orbit around the earth, the moon spins on its axis
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one time
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In a lunar eclipse, the moon
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is in the earth's shadow
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When the size of the visible portion of the moon is decreasing, the moon is
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waxing
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In the crescent phases, the entire moon shines dimly because of
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sunlight reflected off the earth
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THe two moons of Mars are
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Phobos and Deimos
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Compared with the other moons of Jupiter, the four Galilean moons are
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larger
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The rings of Saturn are probably composed of
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billions of pieces of ice and rock
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