Timed quiz 3 Flashcards Preview

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Flashcards in Timed quiz 3 Deck (50):
1

What do asteroids and comets have in common?

They have a similar range of orbital inclinations.
They have nothing in common with each other.
They have similar orbital radii.
They have similar densities.
Most are unchanged since their formation in the solar nebula.

Most are unchanged since their formation in the solar nebula.

2

The combined mass of all the asteroids in the asteroid belt is

about the same as that of Earth.
about the same as that of Jupiter.
about twice that of Earth.
less than that of any terrestrial planet.
more than that of all the planets combined.

less than that of any terrestrial planet.

3

What is a meteorite?

a streak of light caused by a small particle from space burning up in Earth's atmosphere
a streak of light caused by a star moving across the sky
a comet that burns up in Earth's atmosphere
a fragment of an asteroid from the solar system that has fallen to Earth's surface
a small moon that orbits one of the giant planets

a fragment of an asteroid from the solar system that has fallen to Earth's surface

4

What do we call a small piece of solar system debris found on Earth?

meteorite
meteor
cometary fragment
solar system debris
meteoroid

meteorite

5

Most meteorites are

carbon-rich and processed.
rocky and primitive.
carbon-rich and primitive.
iron-rich and processed.
rocky and processed.

rocky and primitive.

6

In order to have a comet named after you, you have to

calculate its orbit and predict when it will return.
be one of the first three discoverers who report it to the International Astronomical Union (IAU).
be a well-known astronomer.
publish a picture of it in an astronomical journal.
be and do all of the above

be one of the first three discoverers who report it to the International Astronomical Union (IAU).

7

When do comets generally begin to form a tail?

between Mercury and Earth's orbit
They always have a tail (until they run out of material).
inside of Jupiter's orbit
inside Mercury's orbit
beyond Jupiter's orbit

inside of Jupiter's orbit

8

The number of comets in the Oort cloud is probably about

a million.
a trillion.
a billion.
a thousand.
a quintillion.

a trillion.

9

What is the typical size of comets that enter the inner solar system?

1 km
1000 km
100 km
10 km
Comet sizes are unknown because their tails obscure the nucleus.

10 km

10

Why won't Pluto collide with Neptune?

It could!
Pluto's orbit never comes anywhere close to Neptune's orbit.
The two planets have an orbital resonance that prevents them from colliding.
Pluto's orbit is completely inside Neptune's orbit.
Pluto's orbit is completely outside Neptune's orbit.

The two planets have an orbital resonance that prevents them from colliding.

11

In the asteroid impact theory of the extinction of the dinosaurs some 65 million years ago, the dinosaurs (and over half of all the other species on Earth at that time) died off largely because

dust settled on the leaves of plants, making them inedible, so the animals died of starvation.
of injuries suffered from direct hits of pieces of the asteroid or comet.
radiation from iridium in the asteroid caused the dinosaurs to die of cancer.
dust injected into the stratosphere from the impact absorbed visible light from the Sun, causing global temperatures to plummet.
the impact caused massive earthquakes and volcanic activity worldwide.

dust injected into the stratosphere from the impact absorbed visible light from the Sun, causing global temperatures to plummet.

12

Which of the following methods has led to the most discoveries of massive planets orbiting near their parent stars?

detecting the gravitational effect of an orbiting planet by looking for the Doppler shifts in the star's spectrum
detecting the starlight reflected off the planet
detecting the shift of the star's position against the sky due to the planet's gravitational pull
detecting the infrared light emitted by the planet
detecting a planet ejected from a binary star system

detecting the gravitational effect of an orbiting planet by looking for the Doppler shifts in the star's spectrum

13

Planets detected via the Doppler technique have been mostly

Earth-mass, in very close orbits.
Jupiter-mass, in Jupiter-like orbits.
a wide range of masses, in edge-on orbits.
Earth-mass, in Earth-like orbits.
Jupiter-mass, in very close orbits.

Planets detected via the Doppler technique have been mostly

Earth-mass, in very close orbits.
Jupiter-mass, in Jupiter-like orbits.
a wide range of masses, in edge-on orbits.
Earth-mass, in Earth-like orbits.
Jupiter-mass, in very close orbits.

14

What are the two main differences between extrasolar planetary systems discovered to date and our Solar System?

extrasolar planet orbits tend to be closer and more eccentric than in our Solar System
extrasolar planet orbits tend to be more eccentric and inclined than in our Solar System
extrasolar planets tend to be bigger and denser than Jupiter
extrasolar planet orbits tend to be closer and more circular than in our Solar System
extrasolar planets tend to be more massive and dense than Jupiter

extrasolar planet orbits tend to be closer and more eccentric than in our Solar System

15

A planet is detected via the Doppler technique. The repeating pattern of the stellar motion tells us

the planet's size.
the orbital period of the planet.
the planet's mass.
the planet's density.
the orbital eccentricity of the planet.

the orbital period of the planet.

16

The depth of the dip in a star's brightness due to the transit of a planet depends most directly on

the size of the planet's orbit.
the planet's size.
the planet's mass.
the planet's density.
the eccentricity of the planet's orbit.

the planet's size.

17

The composition of a planet's atmosphere be measured during a transit by analyzing

the excess emission of starlight at specific wavelengths.
the length and depth of the dip in light during the transit.
the excess absorption of starlight at specific wavelengths.
the wobble in a star's position on the sky.
the amplitude and period of the star's motion.

the excess absorption of starlight at specific wavelengths.

18

How do we think the "hot Jupiters" around other stars were formed?

They formed as gas giants close to the star in the same orbits that they are seen today.
Many planets were formed around the star but coalesced into a single planet close in.
They spun off from the young star when it was rapidly rotating.
They formed as dense, rocky planets close to the star in the same orbits that they are seen today.
They formed as gas giants beyond the frost line and then migrated inwards.

They formed as gas giants beyond the frost line and then migrated inwards.

19

Which of the following is a consequence of the discovery of hot Jupiters for understanding our own Solar System?

It shows that life in the Universe is rare.
It shows that our Solar System is very typical.
It shows that Jupiter is unusually cold.
It shows that our Solar System is very unusual.
It shows that we do not fully understand the formation of our Solar System.

It shows that we do not fully understand the formation of our Solar System.

20

How does the Kepler mission plan to detect Earth-like planets around other stars?

by observing the spectrum of the planet
by measuring the Doppler shift in spectral lines as the central star is tugged to and fro by the planet
by observing the slight dip in brightness of the central star as the planet transits
by measuring the slight shift in position of the central star as it is tugged to and fro by the planet
by directly imaging the planet

by observing the slight dip in brightness of the central star as the planet transits

21

What defines the habitable zone around a star?

the region around a star where liquid water can potentially exist on planetary surfaces
the region around a star where rocky planets form
the region around a star where humans can survive
the region around a star where life exists
the region around a star where the ultraviolet radiation does not destroy organisms on a planetary surface

the region around a star where liquid water can potentially exist on planetary surfaces

22

In 1974, a radio message was sent out from the Arecibo observatory in Puerto Rico. How far has it gotten, approximately?

beyond the Milky Way, to the Andromeda galaxy
not even to the nearest stars
just beyond our Solar System
almost to the center of the Milky Way
just a miniscule fraction of the distance across the Milky Way

just a miniscule fraction of the distance across the Milky Way

23

Grass (that is healthy) looks green because

it transmits green light and emits other colors.
it reflects green light and absorbs other colors.
it absorbs green light and emits other colors.
it emits green light and absorbs other colors.

it reflects green light and absorbs other colors.

24

Which of the following cannot be described by a field?

gravitational forces
radiation pressure
electrical forces
magnetic forces

radiation pressure

25

From lowest energy to highest energy, which of the following correctly orders the different categories of electromagnetic radiation?

visible light, infrared, X rays, ultraviolet, gamma rays, radio
radio, infrared, visible light, ultraviolet, X rays, gamma rays
infrared, visible light, ultraviolet, X rays, gamma rays, radio
radio, X rays, visible light, ultraviolet, infrared, gamma rays
gamma rays, X rays, visible light, ultraviolet, infrared, radio

radio, infrared, visible light, ultraviolet, X rays, gamma rays

26

Consider an atom of gold in which the nucleus contains 79 protons and 118 neutrons. What is its atomic number and atomic weight?

The atomic number is 118, and the atomic weight is 79.
The atomic number is 79, and the atomic weight is 197.
The atomic number is 79, and the atomic weight is 118.
The atomic number is 118, and the atomic weight is 197.

The atomic number is 79, and the atomic weight is 197.

27

The loss of an electron from a neutral helium atom results in

ionized helium.
ionized deuterium.
neutral deuterium.
neutral hydrogen.
ionized hydrogen.

ionized helium.

28

The study of energy levels in atoms is called

quantum mechanics.
general relativity.
particle physics.
classical mechanics.
special relativity.

quantum mechanics.

29

Spectra from neutral atoms compared with spectra from ionized atoms of the same element

have the same sets of spectral lines but different widths for those lines.
are the same.
are slightly redshifted.
are slightly blueshifted.
have different sets of spectral lines.

have different sets of spectral lines.

30

We can learn a lot about the properties of a star by studying its spectrum. All of the following statements are true except one. Which one?

The peak of the star's thermal emission tells us its temperature: Hotter stars peak at shorter (bluer) wavelengths.
We can look at Doppler shifts of spectral lines to determine the star's speed toward or away from us.
We can identify chemical elements present in the star by recognizing patterns of spectral lines that correspond to particular chemicals.
The total amount of light in the spectrum tells us the star's radius.

The total amount of light in the spectrum tells us the star's radius.

31

From laboratory measurements, we know that a particular spectral line formed by hydrogen appears at a wavelength of 121.6 nanometers (nm). The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 121.8 nm. What can we conclude?

The star is moving toward us.
The star is moving away from us.
The "star" actually is a planet.
The star is getting hotter.
The star is getting colder.

The star is moving away from us.

32

Which of the following statements best describes the two principal advantages of telescopes over eyes?

Telescopes can collect far more light with far greater magnification.
Telescopes can see farther without image distortion and can record more accurate colors.
Telescopes can collect far more light with far better angular resolution.
Telescopes collect more light and are unaffected by twinkling.
Telescopes have much more magnification and better angular resolution.

Telescopes can collect far more light with far better angular resolution.

33

Which of the following could not be measured by an observation that uses only imaging?

the number of bright stars in a nearby star cluster
the general shape of an interstellar cloud of gas
the brightness of a star in our sky
the color of a planet
the rate at which a variable star brightens and dims

the rate at which a variable star brightens and dims

34

Which of the following could not be determined by an observation that uses only spectroscopy?

the chemical composition of a distant star
the speed at which a distant galaxy is moving away from us
the rotation rate of a distant star
the size of a distant galaxy
the surface temperature of a distant star

the size of a distant galaxy

35

Which of the following is always true about images captured with X-ray telescopes?

They are always useful for seeing through things.
They are always very pretty.
They are always displayed with the highest possible angular resolution.
They are always displayed in false color.
They are always displayed with north pointing upward in the images.

They are always displayed in false color.

36

What is the purpose of adaptive optics?

to increase the magnification of telescopes on the ground
to improve the angular resolution of telescopes in space
to eliminate the distorting effects of atmospheric turbulence for telescopes on the ground
to allow several small telescopes to work together like a single larger telescope
to increase the collecting area of telescopes on the ground

to eliminate the distorting effects of atmospheric turbulence for telescopes on the ground

37

Why do astronomers need different telescope designs to observe across the electromagnetic spectrum?

Astronomers and engineers enjoy the challenge of making new telescope designs.
Light pollution is worse at radio wavelengths than visible wavelengths.
Photons of different energy behave differently and require different collection strategies.
Telescopes have to adapt to the greater distortion of the atmosphere at shorter wavelengths.
New telescopes incorporate new technology to increase their efficiency.

Photons of different energy behave differently and require different collection strategies.

38

Which of the following wavelength regions cannot be studied with telescopes on the ground?

radio waves
ultraviolet
X rays
both B and C
both A and C

both B and C

39

What does the technique of interferometry allow?

It allows us to determine the chemical composition of stars.
It allows astronomers to make astronomical observations without interference from light pollution.
It allows two or more telescopes to obtain the angular resolution of a single telescope much larger than any of the individual telescopes.
It allows the same telescope to make images with both radio waves and visible light.
It allows two or more telescopes to obtain a total light-collecting area much larger than the total light-collecting area of the individual telescopes.

It allows two or more telescopes to obtain the angular resolution of a single telescope much larger than any of the individual telescopes.

40

In the late 1800s, Kelvin and Helmholtz suggested that the Sun stayed hot thanks to gravitational contraction. What was the major drawback of this idea?

It was proposed before Einstein's theory of general relativity and was therefore incorrect.
It predicted that Earth would also shrink, which would make it impossible to have stable geology on our planet.
It predicted that the Sun would shrink noticeably as we watched it, and the Sun appears to be stable in size.
It is physically impossible to generate heat simply by making a star shrink in size.
It predicted that the Sun could last only about 25 million years, which is far less than the age of Earth.

It predicted that the Sun could last only about 25 million years, which is far less than the age of Earth.

41

What are the appropriate units for the Sun's luminosity?

joules
meters
kilograms
watts
Newtons

watts

42

What is the average temperature of the surface of the Sun?

1 million K
1,000 K
100,000 K
6,000 K
10,000 K

6,000 K

43

Which is closest to the temperature of the core of the Sun?

10 million K
10,000 K
1 million K
100 million K
100,000 K

10 million K

44

Which layer of the Sun do we normally see?

corona
photosphere
radiation zone
chromosphere
convection zone

photosphere

45

Why must the Sun's rate of fusion gradually rise over billions of years?

Fusion reactions decrease the overall number of particles in the core, causing the core to shrink, converting gravitational potential energy into thermal energy, and increasing the rate of fusion.
The rate of fusion is not rising; it is actually decreasing over time.
The radiation produced by fusion reactions that is trapped in the core gradually raises the temperature, increasing the rate of fusion.
The Sun becomes less efficient and must increase the rate of fusion to produce the same amount of energy.
The Sun gets heavier as it gets older, and the stronger inward pull of gravity increases the fusion rate.

Fusion reactions decrease the overall number of particles in the core, causing the core to shrink, converting gravitational potential energy into thermal energy, and increasing the rate of fusion.

46

Which statement best describes the solar neutrino problem?

Solar neutrinos have been detected, but in fewer numbers than predicted by theoretical models.
Theoretical models predict that neutrinos should be produced in the Sun, but no neutrinos have ever been observed to be coming from the Sun.
Our current understanding of fusion in the Sun suggests that all neutrinos should be destroyed before they arrive at Earth, yet neutrinos are being detected.
No one understands how it can be possible for neutrinos to be produced in the Sun.
The term solar neutrino problem refers to the fact that neutrinos are extremely difficult to detect.

Solar neutrinos have been detected, but in fewer numbers than predicted by theoretical models.

47

Why are neutrinos so difficult to detect?

because there are so rare
because they move at nearly the speed of light
because they are so small
because they rarely interact with matter
because they have no mass

because they rarely interact with matter

48

Which of the following statements about neutrinos is not true?

The mass of a neutrino is 30 percent of the mass of an electron.
Neutrinos have a tendency to pass through just about anything without interactions, making them very difficult to detect.
Neutrinos have no electrical charge.
About a thousand trillion neutrinos are passing through your body every second.
Neutrinos are created as a by-product of the proton-proton chain.

The mass of a neutrino is 30 percent of the mass of an electron.

49

Most of the energy produced in the Sun is released in the form of visible light from the photosphere. However, some energy is released from the upper layers of the solar atmosphere. Which of the following best describes where other forms of light are released?

The chromosphere is the source of X rays, and the corona is the source of radio waves.
The chromosphere is the source of infrared light, and the corona is the source of ultraviolet light.
Radio waves can pass directly through the gas which allows us to see the core.
The convection zone is the source of ultraviolet light, and the upper photosphere is the source of X rays.
The chromosphere is the source of ultraviolet light, and the corona is the source of X rays.

The chromosphere is the source of ultraviolet light, and the corona is the source of X rays.

50

What processes are involved in the sunspot cycle?

gravitational contraction of the Sun
wave motions in the solar interior
the interaction of the Earth's magnetic field with that of the Sun
variations of the solar thermostat
the winding of magnetic field lines due to differential rotation

the winding of magnetic field lines due to differential rotation