ASTRO 5 KUDU TEST QUESTIONS WITH
VERIFIED ANSWERS
How has the universe changed as it has moved forward in time? - ANSWER It
has become cooler and less dense
How might fundamental forces (gravity, the weak force, the strong force) be
affected by extremely high temperatures? - ANSWER They become the same
force
What was the approximate mass composition of the universe just before stars
began to form? - ANSWER 75% hydrogen and 25% helium
What is surprising about the universe from the period observed using the cosmic
microwave background? - ANSWER The universe was smoother than expected
What is the earliest time in the universe that we have a fairly strong
understanding of? - ANSWER 10^-27s after the big bang
What occurred about 380,000 years after the big bang? - ANSWER Electrons
merged with nuclei to form atoms
About how long after the big bang were protons and neutrons able to merge
together into nuclei? - ANSWER 3 minutes
How did the horizon of the visible universe in the early universe compare to that
which we have today? - ANSWER The horizon was smaller and got larger as
time went on
When talking about the early stages of the universe what does inflation refer to?
- ANSWER A period of rapid expansion of the universe soon after the big
bang.
, What is thought to be the cause of temperature variations in the cosmic
microwave background? - ANSWER Tiny quantum fluctuations in the early
universe expanded to a macroscopic size by inflation.
Light is a radiant form of energy that travels through space in the form of
fluctuating - ANSWER Electric and magnetic fields
In the equation E\propto \frac{1}{\lambda}E∝λ1 , what does E refer to? -
ANSWER The energy of an individual photon of light
Humans can see the difference in certain wavelengths of light in the form of... -
ANSWER Color
When we see light it sometimes appears to be a longer or shorter wavelength
than it was emitted at, this is a result of what? - ANSWER Doppler shifting
How do we determine the type of an atom? (hydrogen, helium, gold, etc.) -
ANSWER The number of protons in the atom
What must be true of a photon in order for it to interact with the electrons of an
atom? - ANSWER It must have exactly the right amount of energy to take the
electron to another energy level
How does an absorption spectrum differ from an emission spectrum? -
ANSWER An absorption spectrum shows as a pattern of dark lines against a
continuous spectrum whereas an emission spectrum is a pattern of bright lines
against a dark background.
The precise pattern of wavelengths in an absorption or emission spectrum is
___________ - ANSWER a signature of the types of atoms in the object
When light has been redshifted that means that it has... - ANSWER Had its
wavelength increased due to motion away from us
Light is emitted from an atom in the form of photons when... - ANSWER
Electrons fall to a lower energy level.
VERIFIED ANSWERS
How has the universe changed as it has moved forward in time? - ANSWER It
has become cooler and less dense
How might fundamental forces (gravity, the weak force, the strong force) be
affected by extremely high temperatures? - ANSWER They become the same
force
What was the approximate mass composition of the universe just before stars
began to form? - ANSWER 75% hydrogen and 25% helium
What is surprising about the universe from the period observed using the cosmic
microwave background? - ANSWER The universe was smoother than expected
What is the earliest time in the universe that we have a fairly strong
understanding of? - ANSWER 10^-27s after the big bang
What occurred about 380,000 years after the big bang? - ANSWER Electrons
merged with nuclei to form atoms
About how long after the big bang were protons and neutrons able to merge
together into nuclei? - ANSWER 3 minutes
How did the horizon of the visible universe in the early universe compare to that
which we have today? - ANSWER The horizon was smaller and got larger as
time went on
When talking about the early stages of the universe what does inflation refer to?
- ANSWER A period of rapid expansion of the universe soon after the big
bang.
, What is thought to be the cause of temperature variations in the cosmic
microwave background? - ANSWER Tiny quantum fluctuations in the early
universe expanded to a macroscopic size by inflation.
Light is a radiant form of energy that travels through space in the form of
fluctuating - ANSWER Electric and magnetic fields
In the equation E\propto \frac{1}{\lambda}E∝λ1 , what does E refer to? -
ANSWER The energy of an individual photon of light
Humans can see the difference in certain wavelengths of light in the form of... -
ANSWER Color
When we see light it sometimes appears to be a longer or shorter wavelength
than it was emitted at, this is a result of what? - ANSWER Doppler shifting
How do we determine the type of an atom? (hydrogen, helium, gold, etc.) -
ANSWER The number of protons in the atom
What must be true of a photon in order for it to interact with the electrons of an
atom? - ANSWER It must have exactly the right amount of energy to take the
electron to another energy level
How does an absorption spectrum differ from an emission spectrum? -
ANSWER An absorption spectrum shows as a pattern of dark lines against a
continuous spectrum whereas an emission spectrum is a pattern of bright lines
against a dark background.
The precise pattern of wavelengths in an absorption or emission spectrum is
___________ - ANSWER a signature of the types of atoms in the object
When light has been redshifted that means that it has... - ANSWER Had its
wavelength increased due to motion away from us
Light is emitted from an atom in the form of photons when... - ANSWER
Electrons fall to a lower energy level.
