ASTRO 7N EXAM 3 - COMPLETE QUESTIONS AND
DETAILED SOLUTIONS LATEST UPDATE THIS YEAR
JUST RELEASED
Question 1: Hertsprung-russel diagram
Answer:
shows the brightness of the stars on a scale. Plots the luminosity (y-axis)
against the star's surface temperature (x-axis) *the surface temperature
gets hotter from right to left, so the hotter stars are bluer and the cooler
stars are redder. The closer that you get to the y axis, the hotter the
surface temperature gets
Question 2: The spectral class of stars
Answer:
from hottest to coldest they are ranked obafgkm
Question 3: Obafgkm
Answer:
oh be a fine girl kiss me
Question 4: We determine the spectral class of a star using the
Answer:
absorption spectrum
Question 5: The vertical axis of the hertsprung-russel diagram
Answer:
represents the luminosity expressed in terms of the luminosity of the sun
Question 6: Nearest stars
Answer:
,alpha centauri is the closest stars (4.3 light years) from the sun. Most of
the nearest stars are in the lower right of the hr diagram. They are the
cooler and dimmer parts
Question 7: Brightest stars
Answer:
they are warm and very luminous. Sirius they have high luminosity
Question 8: The properties of a star
Answer:
luminosity, mass, size, temperature, and age
Question 9: Size and temperature of a star directly affect
Answer:
luminosity (larger size and higher temperatures reflect a greater
luminosity)
Question 10: Main sequence stars are in a line from the upper left
of the diagram to the lower right with the sun in the middle
Answer:
stars on the main sequence burn the hydrogen and helium into their
cores (proton, proton chain)
Question 11: Mass determines where on the main sequence (red
line) the star lives
Answer:
upper left means the more massive stars and the lower right are the
lower-mass stars
Question 12: What are some stars that are not on the main
sequence?
Answer:
red giants (supergiants) and white dwarfs
, Question 13: What is step two of the proton proton chain
Answer:
the deuterium nucleus (one proton and one neutron) then collides with
another proton and makes a helium 3 nucleus. During this step, some
more energy is released
Question 14: What happens during step three of the proton-proton
chain?
Answer:
the helium 3 nuclei which both contain two protons and one neutron then
collide together to form the helium 4 nuclei
Question 15: Planetary nebula
Answer:
the layers outside fo the core of a low to intermediate-mass star
Question 16: White dwarfs
Answer:
these are held up against gravity but more by the pressure of the
electrons. These are the end states of a former-star's core (about the
size of the earth)
Question 17: More massive stars have how much of a different life
span
Answer:
as the mass increases, the life of the stars becomes shorter
Question 18: The life cycle of a main sequence star
Answer:
at first, the hydrogen core burns when the star is on the main sequence,
but then the helium begins to burn once the hydrogen runs out, then
comes carbon burning, and then nuclei burning in which case it becomes
a red supergiant
DETAILED SOLUTIONS LATEST UPDATE THIS YEAR
JUST RELEASED
Question 1: Hertsprung-russel diagram
Answer:
shows the brightness of the stars on a scale. Plots the luminosity (y-axis)
against the star's surface temperature (x-axis) *the surface temperature
gets hotter from right to left, so the hotter stars are bluer and the cooler
stars are redder. The closer that you get to the y axis, the hotter the
surface temperature gets
Question 2: The spectral class of stars
Answer:
from hottest to coldest they are ranked obafgkm
Question 3: Obafgkm
Answer:
oh be a fine girl kiss me
Question 4: We determine the spectral class of a star using the
Answer:
absorption spectrum
Question 5: The vertical axis of the hertsprung-russel diagram
Answer:
represents the luminosity expressed in terms of the luminosity of the sun
Question 6: Nearest stars
Answer:
,alpha centauri is the closest stars (4.3 light years) from the sun. Most of
the nearest stars are in the lower right of the hr diagram. They are the
cooler and dimmer parts
Question 7: Brightest stars
Answer:
they are warm and very luminous. Sirius they have high luminosity
Question 8: The properties of a star
Answer:
luminosity, mass, size, temperature, and age
Question 9: Size and temperature of a star directly affect
Answer:
luminosity (larger size and higher temperatures reflect a greater
luminosity)
Question 10: Main sequence stars are in a line from the upper left
of the diagram to the lower right with the sun in the middle
Answer:
stars on the main sequence burn the hydrogen and helium into their
cores (proton, proton chain)
Question 11: Mass determines where on the main sequence (red
line) the star lives
Answer:
upper left means the more massive stars and the lower right are the
lower-mass stars
Question 12: What are some stars that are not on the main
sequence?
Answer:
red giants (supergiants) and white dwarfs
, Question 13: What is step two of the proton proton chain
Answer:
the deuterium nucleus (one proton and one neutron) then collides with
another proton and makes a helium 3 nucleus. During this step, some
more energy is released
Question 14: What happens during step three of the proton-proton
chain?
Answer:
the helium 3 nuclei which both contain two protons and one neutron then
collide together to form the helium 4 nuclei
Question 15: Planetary nebula
Answer:
the layers outside fo the core of a low to intermediate-mass star
Question 16: White dwarfs
Answer:
these are held up against gravity but more by the pressure of the
electrons. These are the end states of a former-star's core (about the
size of the earth)
Question 17: More massive stars have how much of a different life
span
Answer:
as the mass increases, the life of the stars becomes shorter
Question 18: The life cycle of a main sequence star
Answer:
at first, the hydrogen core burns when the star is on the main sequence,
but then the helium begins to burn once the hydrogen runs out, then
comes carbon burning, and then nuclei burning in which case it becomes
a red supergiant
