question

Kepler found the orbits of planets are ellipses, not circles.

answer

True

question

The orbits of most of the planets have eccentricities close to zero.

answer

True

question

Kepler based his theories on the precise planetary observations of Tycho Brahe.

answer

True

question

The eccentricity of a perfectly circular orbit is 1.

answer

False

question

Kepler determined the shape of each planet's orbit by triangulation from different points on Earth's orbit, using observations made at many different times of the year.

answer

True

question

Mercury, with a higher eccentricity orbit, should change its orbital speed more than do Venus or Earth.

answer

True

question

A planet (or comet) will speed up as it approaches the Sun

answer

True

question

Transits of Venus were critical in early determinations of the A.U.

answer

True

question

Newton's Laws completely replaced the incorrect work of Kepler.

answer

False

question

Newton's modification of Kepler's Third Law lets us measure the mass of the Sun.

answer

True

question

Kepler's first law worked, where Copernicus' original heliocentric model failed, because Kepler described the orbits as

answer

elliptical, not circular.

question

Tycho Brahe's contribution to Kepler's Laws of Planetary Motion were

answer

his detailed and accurate observations of the planet's position.

question

The most famous prehistoric astronomical observatory is:

answer

Stonehenge.

question

Upon which point do Copernicus and Kepler disagree?

answer

The orbits of the planets are ellipses, with one focus at the Sun.

question

What contribution to astronomy was made by Tycho Brahe?

answer

His observations of planetary motion with great accuracy proved circular orbits could not work

question

Which concept was NOT a part of Kepler's Laws of Planetary Motion?

answer

Epicycles are needed to explain the varying brightnesses of the planets.

question

According to Kepler's third law, the square of the planet's period in years is:

answer

proportional to the cube of its semimajor axis in A.U.

question

What does Kepler's third law imply about planetary motion?

answer

Planets further from the Sun orbit at a slower speed than planets closer to the Sun.

question

A planet whose distance from the Sun is 3 A.U. would have an orbital period of how many Earth-years?

answer

?27

question

The place in a planet's orbit that is closest to the Sun is called

answer

perihelion

question

An accurate sketch of Jupiter's orbit around the Sun would show

answer

a nearly perfect circle.

question

A calculation of how long it takes a planet to orbit the Sun would be most closely related to Kepler's

answer

third law of planetary distances.

question

An asteroid with an orbit lying entirely inside Earth's

answer

has an orbital semimajor axis of less than 1 AU

question

If Earth's orbit around the Sun were twice as large as it is now, the orbit would take

answer

more than two times longer to traverse.

question

Kepler's second law of planetary motion states that a planet in orbit around the Sun will do which of the following?

answer

Sweep out equal areas in equal times

question

How does orbital speed at aphelion compare to the speed at perihelion?

answer

Lower

question

According to Kepler's second law, as a planet or other object moves around its orbit, it sweeps out equal __________ in equal __________.

answer

areas / times

question

According to Kepler's second law, planets and other objects orbiting the Sun move fastest when they are __________.

answer

nearest to the Sun

question

ccording to Kepler's second law, as a planet or other object moves around its orbit, it sweeps out equal __________ in equa

answer

area/times

question

Kepler's third law states that for any planet orbiting the Sun, the orbital period squared (p2 ) is equal to the average orbital distance cubed (a3 ), or p2 = a3 . This implies that _____

answer

a planet with a large average distance from the Sun has a longer orbital period than a planet with a smaller average distance from the Sun

question

Today we rely largely on what technique to precisely measure distances in the solar system?

answer

adar echo timings

question

Newton's gravity would explain why Saturn, so far from the Sun, moves so slowly across the sky.

answer

true

question

It the mass of a body were doubled, its gravity would become 4 × stronger.

answer

False

question

According to Newton's second law, if you double the force acting on a body, the acceleration will double.

answer

True

question

The force of gravity varies with

answer

both product of the two masses and inverse square of the distance separating the two bodies

question

The Law of Universal Gravitation was developed by:

answer

Newton

question

How does Newton's Universal Law of Gravitation explain Kepler's laws?

answer

Universal gravitation implies that the planets will sweep out equal areas in equal times (Kepler's second law) ; Universal gravitation implies that the planets further from the Sun will move more slowly than the planets closer to the Sun

question

If the distance between two asteroids is doubled, the gravitational force they exert on each other will

answer

be one fourth as great.

question

According to Newton's second law, the greater the force exerted on an object, the greater the object's _____.

answer

acceleration

question

Escape velocity is the speed required to

answer

overcome the graviational pull of an object.

question

Combining Newton's and Kepler's laws, we can weigh the Sun, provided we know:

answer

the size of the A.U. and exact length of the year.

question

Kepler's second law implies what about planetary motion?

answer

A planet moves faster when it is closer to the Sun.

question

If the Sun and its mass were suddenly to disappear, Earth would

answer

fly off into space.

question

What would happen to the orbits of each of the planets if the force of gravity was suddenly "turned off"?

answer

Each would move off in a different straight line.

question

In what way did Newton improve Kepler's laws?

answer

He discovered the dependence on mass in the third law.

question

For an object in a circular orbit, how does the velocity depend on the radius of the orbit?

answer

It is inversely proportional to the square root of the radius.

question

According to Newton, planets orbit in ellipses with what at the two foci?

answer

The center of mass and nothing

question

Radio waves, visible light, and x-rays are all a type of electromagnetic radiation

answer

TRUE

question

You would perceive a change in a visible light wave's amplitude as a change in its color.

answer

F

question

The frequency of a water wave gives us its height.

answer

F

question

Gamma Rays are a type of electromagnetic radiation.

answer

T

question

If a new wave arrives on shore every two seconds, then its frequency is 2 Hz.

answer

F

question

The greater the disturbance of the medium, the higher the amplitude of the wave.

answer

T

question

As white light passes through a prism, the red (longer) wavelengths bend less than the blue (shorter) wavelengths, so forming the rainbow of colors.

answer

T

question

A wave's velocity is the product of the

answer

frequency times the wavelength of the wave.

question

While gravity is always attractive, electromagnetic forces are always repulsive.

answer

F

question

Both sound waves and electromagnetic radiation

answer

transfer energy.

question

Which of these is constant for ALL types of electromagnetic radiation in a vacuum?

answer

velocity

question

Which statement gives the relationship between the waves in the electric and magnetic fields in an electromagnetic wave?

answer

They are in phase but perpendicular to each other in space.

question

Electromagnetic radiation

answer

can behave both as a wave and as a particle.

question

Of all the forms of electromagnetic radiation, the one with the lowest frequency is

answer

radio waves.

question

The two forms of electromagnetic radiation that penetrate the atmosphere best are:

answer

visible and radio waves.

question

The hottest objects with temperatures in the millions of degrees Kelvin, give off most of their radiation in which part of the electromagnetic spectrum?

answer

X-ray

question

X-ray telescopes are located in orbit around the Earth because

answer

x-rays don't reach the surface of Earth.

question

The visible color of electromagnetic radiation that has the shortest wavelength is

answer

violet

question

Colors appear different to us because of their photons' different:

answer

frequencies.

question

There are no x-ray telescopes on Earth because

answer

x-rays don't penetrate Earth's atmosphere

question

The radiation our eyes are most sensitive to lies in the color

answer

yellow-green at about 550 nm.

question

Which type of radiation can be observed well from Earth's surface?

answer

visible

question

A blue star has a higher surface temperature than a red star.

answer

T

question

Wein's law relates the peak wavelength of the blackbody to its size. The larger the black body, the shorter its peak wavelength.

answer

F

question

According to Wein's law, the higher the surface temperature of a star, the redder its color.

answer

F

question

What is true of a blackbody?

answer

Its energy peaks at the wavelength determined by its temperature.

question

According to Wien's law, the hottest stars also have

answer

the shortest peak wavelength.

question

A star much cooler than the Sun would appear

answer

RED

question

An observer will measure the wavelength of waves emanating form a source that is moving away as longer than it really is.

answer

T

question

The Doppler Effect is a phenomenon that allows one to measure an object's

answer

radial motion.

question

The light from an object moving tangentially (to your left or right) will exhibit

answer

no shift.

question

If a light source is approaching you at a speed very close to the speed of light, it will appear

answer

bluer than it is.

question

Electromagnetic waves can travel through a perfect vacuum.

answer

T

question

A blackbody emits all its radiation at a single frequency.

answer

F

question

The Doppler effect occurs for all types of wave motion.

answer

T

question

As you drive away from a radio transmitter, the radio signal you receive from the station is shifted to longer wavelengths.

answer

T

question

Two otherwise identical objects have temperatures of 1000 K and 1200 K, respectively. The object at 1200 K emits roughly twice as much radiation as the OBJECT AT 1000 K

answer

T

question

Only a hot, thin gas can produce an emission line.

answer

T

question

The absorption lines for a cool thin gas are identical in color and energy to the emission lines of the same gas if hot enough to glow.

answer

T

question

The spectral lines of each element are distinctive to that element, whether we are looking at emission or absorption lines.

answer

T

question

A low density gas must be hot in order to produce an absorption line.

answer

F

question

What is spectroscopy?

answer

an analysis of the way in which atoms absorb and emit light

question

Typical stellar spectra appear as:

answer

a rainbow, but with some dark lines mixed in.

question

Which of these is the classic continuous spectrum?

answer

a rainbow

question

The Orion Nebula, M-42, is a hot, thin cloud of glowing gas, so its spectrum is:

answer

a few bright lines against a dark background.

question

The three laws dealing with the creation of various spectra are due to:

answer

Kirchhoff

question

The Fraunhofer lines in the solar spectrum are actually:

answer

absorption lines due to the thin outer layer above the photosphere.

question

The element first found in the Sun's spectrum, then on Earth 30 years later, is

answer

helium

question

An incandescent light (glowing tungsten filament) produces:

answer

a continuous spectrum, with the peak giving the temperature of the filament.

question

A neon light (thin hot neon gas in a sealed tube) gives us:

answer

a few bright emission lines, telling us the gas is neon.

question

Compared with a spectrum from a ground-based observation, the spectrum of a star observed from above Earth's atmosphere would show

answer

slightly fewer absorption lines.

question

The visible spectrum of sunlight reflected from Saturn's cold moon Titan would be expected to be

answer

absorption spectrum.

question

Compared with a star having many blue absorption lines, a star with many red and blue absorption lines must be

answer

of different composition than that of the other star.

question

What type of spectrum is emitted by a low-density luminous cloud of hot gases?

answer

Emission

question

A cool, dilute gas between an observer and a continuous hot source will produce which of the following effects?

answer

Dark absorption lines will appear in the spectrum.

question

Which of the following statements about the visible spectrum of the light emitted by the Sun is true?

answer

It consists of hundreds of dark absorption lines superimposed on a bright continuous spectrum that peaks in the yellow, near the center of the VISIBLE LIGHT

question

An x-ray photon has more energy than a visible photon.

answer

T

question

All wavelengths of light travel at the same speed in a vacuum, and carry the same energy per photon.

answer

F

question

The red hydrogen alpha line carries more energy per photon than the blue-green hydrogen beta line does.

answer

F

question

The Balmer lines of hydrogen involve electron transitions from the ground state to higher levels.

answer

F

question

In the Bohr model, the transitions of electrons down to ground state produce the Lyman lines in the ultraviolet.

answer

T

question

The shorter a wave's wavelength, the greater it's energy.

answer

T

question

In the atom, which particles gives the element its identify (atomic number)?

answer

PROTONS

question

High temperatures, rotation, and magnetic fields all tend to broaden spectral lines.

answer

T

question

An electron moves to a higher energy level in an atom after absorbing a photon of a specific energy.

answer

T

question

Light behaves both as a wave and as a particle.

answer

T

question

Fraunhofer lines are emission lines in the solar spectrum.

answer

F

question

Spectral lines of hydrogen are relatively weak in the Sun because the Sun contains relatively little hydrogen.

answer

F

question

An electron can have any energy within an atom, so long as it is above the ground-state energy.

answer

F

question

The energy of a photon is inversely proportional to the wavelength of the radiation.

answer

T

question

In our Sun, the spectral lines of hydrogen are weak, compared to their appearance in hotter stars.

answer

T

question

The line intensity of a spectrum depends both on the abundance of a particular element and its temperature as well.

answer

T

question

The broader the spectral line, the higher the pressure of the gas that is creating it.

answer

T

question

The radial velocity of a star's motion in space can also broaden its spectral lines.

answer

F

question

The Zeeman effect reveals the presence of strong magnetic fields by the splitting of spectral lines.

answer

T

question

The Doppler effect can reveal the rotation speed of a star by the splitting of the spectral lines.

answer

F

question

Spectroscopy of a star can reveal its temperature, composition, and line-of-sight motion.

answer

T

question

The larger the red shift, the faster the distant galaxy is rushing toward us.

answer

F

question

If a fire truck's siren is rising in pitch, it must be approaching us.

answer

T

question

What does a blueshifted spectrum indicate?

answer

The source is moving toward you.

question

Astronomers analyze starlight to determine a star's

answer

ALL ABOVE

question

Compared with slowly rotating stars, the fastest spinning stars have absorption lines that are

answer

broad and fuzzy.

question

Which of the following can not be determined directly from spectral-line analysis?

answer

DISTANCE

question

Which of the following cannot be determined spectroscopically?

answer

Transverse motion

question

It was the Chinese who provided critical ancient data on supernovae and comets.

answer

T

question

Was it possible for the geocentric system of Ptolemy to explain the observed retrograde motion of the planets?

answer

Yes, through a system of epicycles and deferents

question

Planets near opposition

answer

rise in the east.

question

The Ptolemaic model of the universe:

answer

explained and predicted the motions of the planets with deferents and epicycles.

question

The greatest contribution of the Greeks to modern thought was:

answer

the development of scientific inquiry and model building.

question

The Ptolemaic model probably persisted for all these reasons EXCEPT:

answer

it accounted well for Galileo's observations of the phase cycle of Venus.

question

The most accurate Greek attempt to explain planetary motion was the model of:

answer

Ptolemy.

question

The principal culture that transferred Greek astronomical knowledge to Renaissance Europe was:

answer

Islamic.

question

Like the Sun and the Moon, the stars appear to move from west to east from one day to the next.

answer

True

question

Like the Sun and the Moon, the planets always appear to move from west to east from one day to the next.

answer

F

question

When a planet retrogrades, it appears to move westward for weeks at a time.

answer

T

question

As originally stated, the Copernican model did no better a job of predicting planetary behavior than did the Ptolemaic ONE

answer

T

question

Scientists today do not accept the Ptolemaic model because:

answer

the work of Tycho and Kepler showed the heliocentric model was more accurate.

question

On which of these assumptions do Ptolemy and Copernicus agree?

answer

All orbits must be perfect circles.

question

The heliocentric model was actually first proposed by:

answer

Aristarchus.

question

According to Copernicus, the retrograde motion for Mars must occur

answer

at opposition, when the earth overtakes Mars and passes between Mars and the Sun.

question

Which was a contribution to astronomy made by Copernicus?

answer

He laid out the order and relative motion of the known solar system.

question

Which of these was NOT a part of the original Copernican model?

answer

Mercury speeds up at perihelion, and slows down at aphelion.

question

Which of the statements below is part of both the Ptolemaic and Copernican models?

answer

The Moon orbits the Earth once a month.

question

A major flaw in Copernicus's model was that it still had

answer

circular orbits.

question

Which of the following is NOT true about the solar system model of Copernicus?

answer

It used elliptical orbits for the motions of the planets.

question

Who proposed the geocentric view that was accepted and used for more than 18 centuries?

answer

Aristotle

question

The solar system models developed before Kepler's time assumed that the planets followed __________.

answer

circular orbits ; Kepler determined that the planetary orbits are elliptical.

question

Stellar parallax is the _____ in a star's position with respect to more distant background stars, which occurs as the location of the observer changes.

answer

APPARENT SHIFT

question

Galileo's observations of the entire phase cycle of Venus proved that Ptolemy's epicycles could not be correct in keeping Venus between us and the Sun.

answer

T

question

Galileo's observations of sunspots proved the Sun was rotating, like the Earth.

answer

T

question

Which of the following is a contribution to astronomy made by Galileo?

answer

ALL ABOVE

question

Which of these observations of Galileo refuted Ptolemy's epicycles?

answer

the complete cycle of Venus' phases

question

A fatal flaw with Ptolemy's model is its inability to predict the observed phases of

answer

Mercury and Venus.

question

Galileo found the rotation period of the Sun was approximately

answer

A month

question

Which of the following was not one of the discoveries made by Galileo?

answer

The shape of an orbit is an ellipse. This discovery was made by Kepler.

question

The Sun is highest in the sky at __________.

answer

noon

question

Venus's phase is new as viewed from Earth when __________.

answer

Venus is directly between Earth and the Sun

question

For Venus to appear high in the sky at midnight, it would have to be __________.

answer

For Venus to be high in the sky at midnight, it would have to be on the opposite side of our sky from the Sun. But that never occurs, because Venus is closer than Earth to the Sun.

question

In Ptolemy's Earth-centered model for the solar system (not shown), Venus always stays close to the Sun in the sky and, because it always stays between Earth and the Sun, its phases range only between new and crescent. The following statements are all true and were all observed by Galileo. Which one provides evidence that Venus orbits the Sun and not Earth?

answer

We sometimes see gibbous (nearly but not quite full) Venus.

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