astro final
What about Galileo's observations?
- discovered 4 moons of Jupiter, showing that not everything revolved around the sun - observed the rings of Saturn (can get Saturn's mass from that)
if you apply the same force to two carts, the first cart is 100kg the second is 10 kg, the acceleration of the 100 cart would be ____ the acc of the 10.
10 x smaller.
if the temp of an object doubles, the total amount of its thermal radiation will be
16x as big
the earth's mass is about 80 x larger than the moons. What is the ratio of grav force the earth exerts on the moon to the grav force the moon exerts on earth?
1:1
If your weight on Earth is 100 lbs, what would your weight be on a planet with same radius, but 2X mass?
200 lbs
If a period is 125 years, what is the radius of a circular orbit?
25 AU
Which of Keper's laws explains why the Sun has slightly large apparent size in January than July?
2nd law
how many times more chemical energy must a biker expend to reach a speed of 40 kph compared to another biker of the same mass to reach a speed of 20 kph?
4
How old is the sun?
4.5 billion
If the moon were moved to a distance that is 1/4 of its current value, its angular size would be
4x as big
suppose a comet has an elliptical orbit that brings it twice as close to the sun at its closest approach as when it is largest separation. If its speed is 10 km/ second at its largest separation, what will its speed be at its closest?
5 km
The action/ reaction forces refer to Newton's 3rd law:
Acts upon 2 different objects
Why is Venus' surface hotter than Mercury's?
Carbon dioxide in Venus's atmosphere traps heat radiating from its surface making it hotter
What did Tycho Brache discover?
Comets moved outside the Earth's atmosphere AND could detect no parallax so still thought planets go around sun BUT sun goes around earth.
to date, what is the most successful for detecting exoplanets?
Doppler Shift method
What causes seasons?
Earths tilt (inclination) of the planet's rotational axis.
What did Copernicus say?
Heliocentric model (Sun is in center) Retrograde motion is a natural result of SUN BEING AT CENTER!!- planets can appear to change direction in the sky. This is an illusion.
Explain blue and red shifted:
If an object is emitting light and moving toward you, the light you see will be shifted to slightly shorter wavelengths; blue-shifted. If the object is moving away from you, it will be; red-shifted.
What law is this? Planets move in elliptical orbits with the Sun at one focus of the ellipse.
KEPLER's FIRST LAW!!
Why are daily temperature variation on Mars much larger than we experience on Earth
Mar's atmosphere is too thin to insulate the surface
which of the following planets can not be seen at midnight?
Mercury
mercury's avg density is about 1.5 x greater than the moons even though they have similar radii. What does this suggest about M's composition?
Mercury's interior is much richer than the moons
Why don't we have eclipses every month?
Moon's orbit is tipped about 5 deg with respect to the Earth's orbit around the sun. Even if the Moon is new its shadow may pass above or below Earth.
How many forces need to be applied to a body in space to keep it at a constant velocity?
NONE
Newton's law of gravity, the constant G is dependent on?
NOTHING- it is indepentent
Kepler's third law relates to?
P^2= A^3
With Brache's data, what did Kepler discover?
Planets do not move in circles around the sun, they follow ellipses with the sun located at one of 2 foci.
During a lunar eclipse:
The Earth's shadow falls on the Moon.
The circular shape of the Earth's shadow on the Moon led by early astronomers concluded that:
The earth is a sphere.
Galileo's observations of the changing phases of Venus supported what view?
Venus orbits the Sun
What is Newton's third law?
When TWO bodies interact, they create equal and opposite forces on eachother.
If an object moves along a curved path at a constant speed, you can infer that?
a force is acting upon it
which of the following demonstrates the property of inertia
a hockey puck sliding across ice AND a whipping a table cloth
1. Which of the following situation will most closely exhibit the characteristics of a perfect blackbody, as defined by a physicist? a. A small hole in a hollow steel sphere b. The polished surface of a block of gold c. The surface of a piece of transparent glass d. A sheet of steel, painted black
a. A small hole in a hollow steel sphere
1. Neptune's predominantly blue appearance is caused by: a. Absorption of red end of the spectrum of sunlight by methane in its atmospheres b. Aurora emission caused by solar wind particles exciting the atoms and molecules in the atmosphere c. Preferential scattering of light of the solar spectrum by Neptune's atmosphere, similar to the process in the Earth atmosphere d. Reflection of light by water vapor clouds
a. Absorption of red end of the spectrum of sunlight by methane in its atmospheres
1. Which of the following spectrum is observed when white light is shined through a cool gas a. An absorption spectrum b. A continuous spectrum c. An emission spectrum d. None of the above
a. An absorption spectrum
1. How does angular resolution for a given diameter of telescope depend upon wavelength? a. Angular resolution worsens as the wavelength increases b. Angular resolution is independent on the wavelength c. Angular resolution improves as the wavelength increases d. None of the above
a. Angular resolution worsens as the wavelength increases
1. An asteroid failed to form a planet because of a. Gravitational interaction with Jupiter b. Ongoing collisions between asteroids c. An intense solar heating d. The sun magnetic field
a. Gravitational interaction with Jupiter
1. Auroral displays are more often seen a. In a circular region around the north and south geomagnetic poles b. Above areas where tectonic plates are colliding c. At the north and south geographical poles along the Earth's spin axis d. In winter time only
a. In a circular region around the north and south geomagnetic poles
1. The energy of the Sun is generated a. In its central core, by fusion of hydrogen nuclei b. On its surface, but fusion of hydrogen nuclei c. In its central core, by fusion of helium nuclei d. Only in the region of the sunspots
a. In its central core, by fusion of hydrogen nuclei
1. Who developed the first reflecting astronomical telescope? a. Isaac Newton b. Galileo c. Ptolemy d. Copernicus
a. Isaac Newton
1. In which country did Galileo make his astronomical discoveries? a. Italy b. Poland c. England d. USA
a. Italy
1. The cold structure of Venus can best be described as a. Perpetual thick cloud layer with a haze layer under it and clear air below this, down to the surface b. Perpetual thick cloud layer extending to ground level c. Isolated cloud systems constantly forming and dissipating with clear sky between them d. Mostly clear sky with occasional dust clouds
a. Perpetual thick cloud layer with a haze layer under it and clear air below this, down to the surface
1. The ionized gas tail of a comet is always aligned with a. The comet-sun line b. The line between the comet and the nearest planet c. The comet direction of motion d. The celestial equator
a. The comet-sun line
1. The temperature of the corona of the Sun a. Very hot, millions K b. Very cool, since it is the furthest from the heat source c. About 5800K d. 2.7K
a. Very hot, millions K
1. Water vapor in Venus atmosphere a. Was destroyed by the Sun's UV light b. Was never present in the planet's history c. Responsible for Venus covered in clouds d. Is strongly radioactive
a. Was destroyed by the Sun's UV light
1. Particles in Saturn's main ring are made of (or covered with) a. Water ice b. Carbon dioxide c. Metallic hydrogen d. Iron needles
a. Water ice
1. What causes Jupiter and Saturn to have substantially larger radii at their equator than at their poles? a. They spin fast b. High energy storms c. Intense magnetic fields d. Collisions with other planets
a. they spin fast
1. Water vapor in Venus atmosphere a. was destroyed by the Sun's UV light b. was never present in the planet's history c. responsible for Venus covered in clouds d. is strongly radioactive
a. was destroyed by the Sun's UV light
If 2 different objects of different mass are dropped from a window what will they have the same of?
acceleration
the purpose of adaptive optics is to make telescopes
adjust for the distortions caused by earths atmosphere
why is it that on Earth a feather will fall at a slower rate than a rock?
air resistance reduces the net downward force on the feather
what kinds of info have been determined by observing planetary transits
all the above
which of the following features of the solar system does the solar nebula theory explain
all the above
looking down on the solar system from above the suns north pole, ________ planets orbit counterclockwise and _________ planets spin counterclockwise
all- most
our knowledge of composition of earth's core comes from
analysis of earthquake waves
A high mountain top such as Mauna Kea in Hawaii is a good site for an infrared observatory because it is a. Closer to the stratospheric ozone layer b. Above most of the moisture in Earth's atmosphere c. Far from city noise d. Further from city lights
b. Above most of the moisture in Earth's atmosphere
1. Solar flares arise from: a. Nuclear bursts in the photosphere of solar corona b. Annihilation reconnection of magnetic fields c. Comets hitting the sun d. Volcanic activity of the sun
b. Annihilation reconnection of magnetic fields
1. Why is it relatively difficult to observe Mercury from Earth? a. Because its surface is always glowing from the intense ultraviolet sunlight b. Because it is a small object and always appears close to the Sun in the sky c. Because its surface is completely covered by clouds d. Because its orbit is such that it is always on the opposite side of the Sun to the Earth
b. Because it is a small object and always appears close to the Sun in the sky
1. How was Neptune discovered? a. By accident, by an astronomer who was conducting a sky survey b. By a careful application of Newton's laws to the motion of other planets c. By a careful application of general relativity to the motion of other planets d. By a space mission
b. By a careful application of Newton's laws to the motion of other planets
1. The Roche limit is the a. Smallest mass a planet can have b. Distance a planet's tidal force equals a moon own gravity c. Largest stable orbit of a planet d. Depth astronomers can see into a planet's cloud
b. Distance a planet's tidal force equals a moon own gravity
1. Where in the solar system would you look for liquid hydrogen? a. Nowhere, because it is not cold enough anywhere in the solar system to liquefy hydrogen b. In the deep interiors of Jupiter and Saturn c. On the polar caps of Mars d. At the polar region of the Moon
b. In the deep interiors of Jupiter and Saturn
1. Which of the following are you least likely to find in an asteroid? a. Metallic inclusions b. Liquid water c. Rocky material d. Carbon-based material
b. Liquid water
1. How many forces need to be applied to a body in empty space to keep it moving with a constant velocity a. Two unequal forces b. None c. One force, in the direction of motion d. None of the above
b. None
1. The asteroid belt is believed by most astronomers to be composed of a. Icy fragments similar to the nuclei of comets b. Rocky debris left over from the formation of solar system c. Genuine leather d. The remnants of a gaseous planet, disrupted by an impact
b. Rocky debris left over from the formation of solar system
1. What will happen with the gravitational force between the Sun and the Earth, if the Sun collapses into 1 solar mass black hole? a. The force will increase enormously b. The force will stay the same c. The force will decrease by the ratio of the present solar radius to the radius of the black hole d. The force will increase by the ratio of the present solar radius to the radius of the black hole
b. The force will stay the same
1. Which planet has its spin axis tilted 98 degrees from the vertical? a. Mercury b. Uranus c. Mars d. Jupiter
b. Uranus
earth's average density is
between density of rock and iron
Some astronomers think Venus once has oceans. If that was true, where did the water go? The water
boiled, and the sunlight broke into hydrogen and oxygen
a satellite orbiting a planet in a circular path at a constant speed has what kind of energy
both kinetic and potential
astronauts inside the INTL space station appear weightless becasue
both space station and astronauts are orbiting earth therefore the astronauts appear weightless because both objects are falling together towards Earth
What evidence suggests that liquid water was once on the Martian surface?
branching channels in the shape of river beds
Over the course Mercurian year, the suns motion across the sky is
briefly travels W to E, but otherwise E to W
how do astonomers estimate the size of most asteroids
by measuring the amount of light they reflect
1. Jupiter is about 5 times farther from the Sun than the Earth is. About how long is Jupiter's year? (very approximately?) a. 3 Earth years b. 1100 Earth years c. 11 Earth years d. 30 Earth years
c. 11 Earth years
1. The early phases of planetary formation into proto-planets are characterized by a. Breaking apart of large objects into planets b. Condensation of hot gas clouds c. Accretion of small particles by gravitational attraction and collisions d. Violent collapse of matter under gravity
c. Accretion of small particles by gravitational attraction and collisions
1. The early phases of planetary formation into protoplanets are characterized by a. Breaking apart of large objects into planets b. Condensation of hot gas clouds c. Accretion of small particles by gravitational attraction and collisions d. Violent collapse of matter under gravity
c. Accretion of small particles by gravitational attraction and collisions
1. What does Uranus look like from space? a. Reddish belts and light cones parallel to equator b. Yellowish due to sulfur-rich clouds c. Blue-green and featureless d. Purple
c. Blue-green and featureless
1. In what way are the atmospheres of Mars and Venus similar to each other? a. Temperature b. Pressure c. Chemical composition d. Density
c. Chemical composition
1. The source of excess heat emitted by Jupiter, in addition to that absorbed as sunlight and reemitted, is thought to be a. Heat generated by magnetic fields b. Chemical reactions in methane and oxygen in the atmosphere c. Gravitational potential energy released as heat d. Heat caused by friction between winds at mid-latitudes
c. Gravitational potential energy released as heat
1. Much of the mass of our Galaxy appears to be in the form of "dark matter," which can be detected at present because a. It blocks out the light from the stars b. It emits a lot of visible light c. Its gravitational pull affects orbital motion in the Galaxy d. It repels stars
c. Its gravitational pull affects orbital motion in the Galaxy
What gives Neptune and Uranus their blue color? a. Objects at such low temperatures take on blue color b. Water molecules reflect blue light c. Methane gas absorbs the longer wavelength of visible light d. Interplanetary dust absorbs all red light
c. Methane gas absorbs the longer wavelength of visible light
1. Most of the mountains on Earth have been produced by a. Volcanic eruptions b. Asteroid impacts c. Tectonic plates colliding as they move d. Wrinkling of the crust as the Earth interior cools and contracts
c. Tectonic plates colliding as they move
1. Retrograde motion of a planet when viewed from Earth is caused by a. The planet's elliptical orbital path b. The relative motions of Sun and planet c. The relative motion of Earth and planet d. The inclination of the planet's orbit to the ecliptic plane
c. The relative motion of Earth and planet
1. Sunspots appear dark because: a. They have lower densities b. They have lower rotation rates c. They have lower temps d. They have high concentration of iron
c. They have lower temps
What is the main reason for placing astronomical telescopes and detectors on satellites? a. To get closer to the objects being viewed b. To avoid light pollution from cities and other built-up areas c. To get above the absorption, reflection and scattering in the Earth's atmosphere d. To avoid effects of gravity on CCD detectors
c. To get above the absorption, reflection and scattering in the Earth's atmosphere
1. Acceleration of a body is its rate of change a. Mass b. Weight c. Velocity d. Position
c. Velocity
A big problem for infrared observations is a. Car smog b. Global warming c. Water vapor d. Light pollution
c. Water vapor
1. Galileo's observations of the sky with his telescope included: a. the discovery of the aurora, or the northern lights b. the discovery of Pluto c. the fact that Venus showed phases, similar to those of the Moon d. the discovery of retrograde motion in planets
c. the fact that Venus showed phases, similar to those of the Moon
why is venus's surface hotter than mercurys
carbon dioxie in V atmosphere traps heat radiating from its surface, making it warmer
In what way are the atmospheres of Mars and Venus similar?
chemical compositions
Which of the following is a place where you would never expect to see one of the 5 bright planets?
close to the North Star
Kepler's second law states a planet moves faster when it is:
closest to the sun
1. How much longer can the Sun continue to generate energy by nuclear reactions in its core? a. About 5 billion years b. About 5 thousand years c. About 500 years d. About 500 billion years
d. About 500 billion years
1. Where in the universe would you look for Ganymede? a. Around Mars b. Around Jupiter c. In the asteroid belt d. Around Pluto
d. Around Pluto
The limit of the resolution of the biggest ground based telescope is due to a. Diffraction b. Reflection of light from the telescope mirror c. The focal length d. Atmospheric distortion of light propagation
d. Atmospheric distortion of light propagation
1. A satellite orbiting a planet in a circular path at a constant speed has what kind of energy a. Only potential energy b. Only kinetic energy c. No kinetic or potential energy d. Both kinetic and potential energies
d. Both kinetic and potential energies
1. The cores of Jupiter and Saturn are a. High density gas b. Balls of extremely cold liquefied gases c. Icy bodies d. Hot rock and iron of the Earth size
d. Hot rock and iron of the Earth size
1. Kepler's second law states that a planet moves fastest when it a. Passes through the minor axis b. Is farthest from the sun c. Is moving perpendicular to the plane of its orbit d. Is closet to the sun
d. Is closet to the sun
1. Detailed observation of Jupiter's rotation suggests that a. Its slowing down its noticeable at the present time b. It rotates as a solid body c. It rotates in two separate parts, equatorial regions in the direction opposite to polar regions d. It is not a rigid object, because equatorial regions rotate faster than polar regions
d. It is not a rigid object, because equatorial regions rotate faster than polar regions
1. The Earth has slightly higher average density than Mercury because a. The Earth has a larger iron core in proportion to its size than Mercury has b. The Earth has much denser atmosphere than Mercury c. Mercury's interior has expanded slightly because of radioactive heating, reducing its density d. The Earth is more massive than Mercury and therefore it is more gravitationally compressed
d. The Earth is more massive than Mercury and therefore it is more gravitationally compressed
1. Space-based telescopes have to be used to observe which type of electromagnetic radiation? a. Radio b. Infrared c. Visible d. X-rays
d. X-rays
1. If the radius of the sun were doubled, the gravitational force on Mars due to the sun would be: a. 4 times its present value b. 16 times its present value c. twice its present value d. stay the same
d. stay the same
Ancient greeks are not credited with?
detecting the parralax of stars
What did Ptolemy improve?
did Ptolemy improve? Ptolemy= geocentric model (Earth was in center) He included epicycles
Occam's razor is used to
discriminate between models based on their simplicity
why does mercury have so many craters and earth so few
erosion and plate tectonic activity have destroyed most of the craters on earth
why does mercury have so many creators and earth so few?
erosion and plate tectonic activity have destroyed most of the creators on earth
You see a spacecraft moving w/ constant velocity. What must be true about the forces acting upon the spacecraft?
forces may be acting on it- but net force must be 0
the scarps that cut across the surface of Mercury probably were
formed when the crust buckled as Mercury cooled
when the sunlight has is passed through a spectroscope an absorption spectrum is observed because the sun
has a hot interior that shines through cooler low density gas
the slow shifts of our planets are thought to arise from
heat from the interior causing convective motion which pushes on the crust
below the thick clouds of jupiter and saturn is a layer of liquid hydrogen hydrogen is in a liquid form due to
high pressures
atmospheric refraction makes the sun look
higher in the sky
the amount of infrared energy emitted by jupiter is about twice as great as the amount of sunlight the planet absorbs. which is significance ?
implies that there are significant energy sources with in jupiter
astronomers use interferometers to
improve the ability to see finer details in sources
Which of the following did the models of Copernicus and Kepler have in common?
inner planets move faster than outer planets
Gravity
is the attraction between all objects that have mass
an astronomer finds that the visible spectrum of an object show bright emission lines, what can she conclude?
it contains hot, relatively tenuous gas
at the time it was proposed, what was most convincing about Coperiunes model of the solar system versus earlier models
it explained retrograde motion more simply and naturally
Mercury's core is unusual in that
it is relatively large compared to Mercury's size
why is pluto not considered a planet
it orbits inside the Kuiper belt
What feature of Venus best explains its lack of magnetic field?
its dense atmosphere
starting with the sun and moving outward, what is the first planet that formed beyond the point where water condenses
jupiter
the Doppler shift method for detecting the presence of exoplanets is best able to detect
low mass planets far from the star
which of the planets probably has the coldest core
mars
why are daily temp variations on mars much larger than we experience on earth
mars atmosphere is too thin to insulate the surface
Newton stated a force applied to object in space, the acceleration of that object depends on its what?
mass
what physical quantity is used to determine the amount of inertia?
mass
given the characteristics of exoplanets what are the most likely conclusions we might draw about how the solar nebula theory should be modified for the formation of other planetary systems>
massive planets usually arnt composed of light elements
other than earth which 3 planets are primary rock with iron cores?
mercury, Venus, mars
mercuy's avg density is about 1.5x grater than the moons even though they have similar radii. Suggests what?
mercuy's interior is much richer in iron than the moons
what gives neptune and uranus their blue color
methane gas absorbs longer wavelengths of visible light
the lunar maria have a composition most like the
moons mantel
what evidence indicates that part of earth's interior is liquid
no S-type waves are detectable at some locations after an earthquake
which of the following explains the advantage of the hubble space telescope compared with ground based telescopes?
not effected by atmospheric scintillation
Newton stated a constant continuous force applied to a body in space has?
only constant acceleration
low average density of saturn suggest that
saturn contains large quantities of light elements such as hydrogen and helium
a telescope resolution quantifies its ability to
see finer details in sources
Over the course of many night, a planet in retrograde motion will
shift east to west of the celestial sphere
The acceleration due to gravity on the moon is what compared to the Earth?
significantly smaller than the Earth
what feature of venus best explains lack of magnetic field
slow rotation rate
suppose a number of planets all have the same mass but different sizes and temperatures which planet is most likely to retain thick atmosphere
small and cool
compared to the lunar highlands, the lunar maria are
smoother and younger
terrestrial planets are characterized by what property
solid surfaces
star A has a wavelength of max emission at 500 nm while star B has a wavelength max emission at 600 nm. What can we conclude?
star A is hotter
if your are observing with a reflecting telescope which would increase the resolution
switch to a telescope that has a bigger mirror
The color of a star indicates?
temperature
the color of a star indicates:
temperature
a rocket blast propellent out of its thruster and "lifts off" heading into space. What provided the force to "lift" the rocket?
the action of the propellent accelerating down, giving a reaction force to the rocket
one explanation of why the planets near the sun are composed mainly of rock and iron is
the high temps in the inner part of the solar system prevented ices and gases from condensing near the sun
the mass of a 5 kg would be ______ if located in deep space, far away from any star or planet
the same
which of the following cases does not describe an acceleration?
the space shuttle being towed at a steady pace
what do astronomers need to know before they can estimate the relative amount of different elements in a stars atmosphere?
the strength of absorption from each elements lines and the temperature of the stars atmosphere
more than 99% of the mass of the solar system is contained in
the sun
Earth's distance from the sun varies as it orbits the Sun. Consequently,
the sun has a larger angular size when Earth is closer to the sun
Which of the following is not true of Tharsis Bulge?
the surface material is relatively older
What evidence is there that the surface of Venus was covered by giant flows of lava a hundred million years ago?
there are relatively few impact craters on Venus
what evidence is there that the surface of venus was covered by giant flows of lava hundreds of years ago
there are relatively few impact creators on venus
urans and neptune are sometimes ice giants not gas giants because of
they are composed of molecules that condense into icy planitesmals at their distance from the sun!
Galilao discovery of Jupiter's moons was surprising because
they did not orbit Earth
what is unusual about the magnetic fields of uranus and neptune
they point at a large angle to their rotation axis
the numerous crators we see on solid surfaces are evidence that
they were bombarded in their youth by many solid objects
astroids
vary largely in size
water vapor in venus atmosphere
was probably destroyed by suns UV light
Water vapor in Venus's atmosphere
was probably destroyed by the Sun's UV light
The force or gravity is responsible for what?
weight
which type of electromagnetic radiation must be observed using a space-based telescope
x-rays
