Download 1. This question is about some of the properties of Barnard`s star

1.
This question is about some of the properties of Barnard’s star.
Barnard’s star, in the constellation Ophiuchus, has a parallax angle of 0.549 arc-second as
measured from Earth.
(a)
With the aid of a suitable diagram, explain what is meant by parallax angle and outline
how it is measured.
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(6)
(b)
Deduce that the distance of Barnard’s star from the Sun is 5.94 ly.
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(2)
(c)
The ratio
(i)
apparent brightness of Barnard' s star
is 2.6 × 10–14.
apparent brightness of the Sun
Define the term apparent brightness.
1
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(2)
(ii)
Determine the value of the ratio
luminosity of Barnard' s star
(1 ly = 6.3 ×
luminosity of the Sun
104 AU).
(4)
(d)
The surface temperature of Barnard’s star is about 3 500 K. Using this information and
information about its luminosity, explain why Barnard’s star cannot be
(i)
a white dwarf.
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(1)
(ii)
a red giant.
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(1)
(Total 16 marks)
2.
This question is about the properties of the star Arcturus.
The following data is for the star Arcturus.
(a)
Distance from
Earth / m
Apparent
magnitude
Absolute
magnitude
3.39 × 1017
–0.1
–0.3
Spectral type Luminosity / W
K
3.8 × 1028
Explain the difference between apparent magnitude and absolute magnitude.
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(2)
2
(b)
State and explain, with reference to the data, whether Arcturus would be visible without the
aid of a telescope on a clear night.
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(1)
Techniques for determining stellar distances include the use of stellar parallax, spectroscopic
parallax and Cepheid variables.
(c)
(i)
Calculate the distance, in pc, of Arcturus from the Earth.
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(1)
(ii)
State and explain which technique would be most suitable for determining the
distance to Arcturus.
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(2)
(iii)
Outline the method you have chosen in your answer to (c)(ii).
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(4)
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(d)
State how it may be deduced from the data that the surface temperature of Arcturus is lower
than that of the Sun.
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(2)
The temperature of Arcturus is 4000 K.
(e)
Calculate
(i)
the surface area of Arcturus.
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(2)
(ii)
the radius of Arcturus.
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(2)
(iii)
the wavelength at which the light from Arcturus has its maximum intensity.
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(2)
(f)
Using your answers to (e) deduce the stellar type to which Arcturus belongs.
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(2)
4
(Total 20 marks)
3.
This question is about stellar magnitude and brightness.
(a)
State what is meant by apparent magnitude.
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(1)
(b)
Define absolute magnitude.
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(2)
(c)
Explain why a star with an apparent magnitude of 6 radiates approximately 2.5 times more
light power than a star with an apparent magnitude of 7.
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(3)
(d)
The star Capella has an apparent magnitude of +0.05 and its distance from Earth is 14 pc.
Estimate its absolute magnitude.
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(3)
(Total 9 marks)
4.
This question is about stellar observations.
(a)
Define the following terms.
(i)
Luminosity
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5
.........................................................................................................................
(1)
(ii)
Apparent brightness
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(1)
(b)
spectrum and temperature of a certain star are used to determine its luminosity to be
approximately 5.0 1031 W. The apparent brightness of the star is 1.4 10–9 W m–2. These
data can be used to determine the distance of the star from Earth.
(i)
State the name of this technique used to determine distances to stars.
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(1)
(ii)
Calculate the distance of the star from Earth in parsec.
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(3)
(c)
Distances to some stars can be measured by using the method of stellar parallax.
(i)
Outline this method.
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6
(ii)
Modern techniques enable stellar parallax angles as small as 5.0 10–3 arc-second to
be measured. Calculate the maximum distance that can be measured using the
method of stellar parallax.
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(1)
(Total 11 marks)
5.
This question is about luminosity.
(a)
Define luminosity.
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(1)
(b)
The sketch-graph below shows the intensity spectrum for a black-body at a temperature of
6000 K.
intensity
0
0
wavelength
On the axes above, draw a sketch-graph showing the intensity spectrum for a black-body at
8000 K.
(2)
7
(c)
A sketch of a Hertzsprung-Russell diagram is shown below.
luminosity
temperature
On the diagram above, identify the
(i)
(ii)
(iii)
main sequence (label this M);
red giant region (label this R);
white dwarf region (label this W).
(2)
(d)
In a Hertzsprung-Russell diagram, luminosity is plotted against temperature. Explain why
the diagram alone does not enable the luminosity of a particular star to be determined from
its temperature.
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(3)
(Total 8 marks)
6.
This question is about stellar magnitudes and stellar distances.
(a)
Define
(i)
apparent magnitude;
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.........................................................................................................................
(1)
(ii)
absolute magnitude.
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(1)
(b)
Star A has an apparent magnitude of 5.0 and is 100 pc from Earth. The luminosity of star A
is 4.0 times the luminosity of star B. The apparent brightness of star A is 100 times greater
than the apparent brightness of star B.
Deduce that
(i)
star B is 500 pc from Earth;
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(3)
(ii)
the absolute magnitude of star A is 0.
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(2)
(Total 7 marks)
9
7.
This question is about magnitude and apparent brightness.
(a)
Define apparent brightness and apparent magnitude.
Apparent brightness: ...................................................................................................
...................................................................................................
Apparent magnitude: ...................................................................................................
...................................................................................................
(2)
(b)
The table gives information on the peak absolute magnitude and the peak apparent
brightness of two Cepheid stars.
star
(peak) absolute
magnitude
(peak) apparent
brightness
Delta Cephei
–3.47
9.0×10–10Wm–2
Zera Geminorum
–4.13
7.2×10–10Wm–2
State and explain whether Delta Cephei or Zeta Geminorum
(i)
appears brighter from Earth.
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...........................................................................................................................
(1)
(ii)
is closer to Earth.
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(2)
(c)
The luminosity of a Cepheid star is variable. Outline the reason for this variation.
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(2)
The graph shows the variation with period of the peak luminosity of Cepheid stars.
10000
Luminosity
1000
100
1
10
Period/days
100
The luminosity is given in terms of the solar luminosity of 3.9×1026W.
(d)
(i)
Outline how data from the graph may be used to determine the distance of a galaxy
from Earth.
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(3)
11
(ii)
The peak apparent brightness of Zeta Geminorum is 7.2×10–10Wm–2 and the period
of variation of luminosity is approximately 10 days.
Use data from the graph on previous page to deduce that the distance to Zeta
Geminorum from Earth is about 1.1×1019 m.
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(2)
(Total 12 marks)
8.
This question is about Cepheid variables.
(a)
Define
(i)
luminosity.
...........................................................................................................................
(1)
(ii)
apparent brightness.
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(1)
(b)
State the mechanism for the variation in the luminosity of the Cepheid variable.
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(1)
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The variation with time t, of the apparent brightness b, of a Cepheid variable is shown below.
b / 10 –10 W m –2 1.3
A
1.2
1.1
1.0
0.9
B
0.8
0
1
2
3
4
5
6
7
8
9
10
Time / days
Two points in the cycle of the star have been marked A and B.
(c)
(i)
Assuming that the surface temperature of the star stays constant, deduce whether the
star has a larger radius after two days or after six days.
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(2)
(ii)
Explain the importance of Cepheid variables for estimating distances to galaxies.
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(3)
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(d)
(i)
The maximum luminosity of this Cepheid variable is 7.2 × 1029 W. Use data from
the graph to determine the distance of the Cepheid variable.
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(3)
(ii)
Cepheids are sometimes referred to as “standard candles”. Explain what is meant by
this.
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(2)
(Total 13 marks)
9.
This question is about Cepheid variables.
The characteristics of a Cepheid variable were first observed in 1784.
(a)
(i)
Describe the characteristic by which a Cepheid variable may be identified from
Earth.
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(2)
(ii)
Outline the cause of this characteristic.
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(2)
A particular Cepheid variable is found to have an average value of apparent magnitude of 5.2 and
a time period of pulsation of 50 days. Apparent magnitude m is related to absolute magnitude M
14
and distance d (measured in parsec) by the expression
m – M = 5lg d – 5.
(b)
(i)
Distinguish between apparent magnitude and absolute magnitude.
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(2)
The graph below shows how the absolute magnitude M of some Cepheid variables varies with
time period T of pulsation.
–8
–7
–6
–5
M
–4
–3
–2
–1
1
(ii)
2
3
4
5
6
7 8
10
T / day
20
30
40
50
60 70 80
100
Use the graph to obtain a value for the absolute magnitude of this Cepheid variable
and hence determine its distance from Earth.
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(3)
(Total 9 marks)
15
10.
This question is about the nature of certain stars on the Hertzsprung-Russell diagram and
determining stellar distance.
The diagram below shows the grid of a Hertzsprung-Russell (H-R) diagram on which the
positions of the Sun and four other stars A, B, C and D are shown.
106
B
A
104
102
Luminosity (L)
(Sun L = 1)
1
Sun
10–2
C
10–4
D
10–6
25000
10000
8000
6000
5000
4000 3000
Surface temperature (T / K)
(a)
State an alternative labelling of the axes,
(i)
x-axis .................................................................................................................
(1)
(ii)
y-axis .................................................................................................................
(1)
(b)
Complete the table below.
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Star
Type of star
A
B
C
D
(4)
(c)
Explain, using information from the H-R diagram, and without making any calculations,
how astronomers can deduce that star B is larger than star A.
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(3)
(d)
Using the following data and information from the H-R diagram, show that star B is at a
distance of about 700 pc from Earth.
Apparent visual brightness of the Sun
Apparent visual brightness of star B
Mean distance of the Sun from Earth
1 parsec
= 1.4 × 103 W m–2
= 7.0 × 10–8 W m–2
= 1.0 AU
= 2.1 × 105 AU
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(4)
(e)
Explain why the distance of star B from Earth cannot be determined by the method of
17
stellar parallax.
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(1)
(Total 14 marks)
11.
A partially completed Hertzsprung-Russell (H-R) diagram for some stars in the Milky Way
galaxy is shown below.
luminosity
temperature
(a)
On the diagram,
(i)
identify the regions associated with red giants (label the region R) and white dwarfs
(label the region W).
(1)
(ii)
mark with the letter S the approximate present position of the Sun.
(1)
(iii)
draw the evolutionary path of the Sun from its present position to its ultimate
position.
(2)
(b)
At the end of its main sequence lifetime, a star of approximately ten times the mass of the
Sun will start to produce energy at a much higher rate and its surface will become cooler.
18
Outline how it is possible for the star to be producing more power and yet its surface is
cooling.
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(2)
(Total 6 marks)
12.
This question is about the evolution of stars.
The diagram below shows a grid on which a Hertzsprung-Russell diagram could be drawn. The
present positions of the Sun and another Main Sequence star A are shown.
106
A
10
4
10 2
Sun
1
Luminosity (L)
(Sun L = 1)
10–2
10–4
10–6
40 000
10 000
6 000
4 000
3 000
surface temperature (T/K)
The mass of star A is about 15 times the mass of the Sun.
(a)
On the diagram above, draw the evolutionary path of the Sun and the evolutionary path of
19
star A as both stars leave the Main Sequence.
(4)
(b)
When stars with masses of about eight times that of the Sun leave the Main Sequence, they
may end up in the same region of the Hertzsprung-Russell diagram as the Sun when it
leaves the Main Sequence. Explain, with reference to the Chandrasekhar limit, why this is
so.
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(4)
(c)
State two main changes that take place in nucleosynthesis when a star of about eight times
the solar mass leaves the Main Sequence.
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(2)
(Total 10 marks)
13.
This question is about the possible evolution of the Universe.
20
The diagram below is a sketch graph that shows three possible ways in which the size of the
Universe might change with time.
Size of Universe
Time
Depending on which way the size of the Universe changes with time, the Universe is referred to
either being open or flat or closed.
(a)
On the diagram, identify each type of Universe.
(3)
(b)
Complete the table below to show how the mean density ρ of each type of Universe is
related to the critical density ρ0.
Type of Universe
Relation between ρ and ρ0
Open
Flat
Closed
(3)
(Total 6 marks)
14.
This question is about galactic redshift, the Hubble constant and the age of the Universe.
(a)
State how the observed redshift of light from many distant galaxies is explained.
21
.....................................................................................................................................
(1)
(b)
Using the axes below sketch a graph to show how the recessional speed v between galaxies
varies with the distance d between them. (Please note this is a sketch graph; you do not
need to add any numerical values.)
v
0
d
(1)
(c)
State how the Hubble constant is determined from such a graph.
.....................................................................................................................................
(1)
(d)
A value for the Hubble constant is 100 km s–1 Mpc–1. Use this value to estimate the age of
the Universe in years. (1 Mpc ≈ 3 × 1019 km, 1 year ≈ 3 × 107 s)
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(2)
(Total 5 marks)
15.
This question is about the evolution of stars.
(a)
Outline the process that provides the source of energy for stars while on the main sequence.
22
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(2)
(b)
State the conditions required for the above process to take place.
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(1)
(c)
State the reason why stars leave the main sequence.
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(1)
(d)
Main sequence stars eventually evolve to form red giants. With reference to the
Chandrasekhar limit, describe and distinguish between the subsequent evolutionary paths
of red giant stars that have evolved from main sequence stars of mass
(i)
about two times that of the Sun.
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(3)
(ii)
about ten times that of the Sun.
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(3)
(Total 10 marks)
16.
This question is about the Big Bang model.
(a)
Describe what is meant by cosmic background radiation.
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(2)
(b)
Explain how cosmic background radiation is evidence in support of the Big Bang model of
the universe.
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(2)
(c)
State one other piece of evidence in support of the Big Bang model.
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(1)
(d)
A student makes the statement that “as a result of the Big Bang, the universe is expanding
into a vacuum”. Discuss whether the student’s statement is correct.
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(2)
(Total 7 marks)
17.
This question is about various bodies in the universe.
(a)
Briefly describe the nature of a star.
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(2)
(b)
Distinguish between a constellation and a galaxy.
Constellation: ............................................................................................................
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Galaxy:
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(4)
(Total 6 marks)
18.
This question is about the mean density of matter in the universe.
(a)
Explain the significance of the critical density of matter in the universe with respect to the
possible fate of the universe.
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(3)
The critical density ρ0 of matter in the universe is given by the expression
2
3H 0
ρ0 =
,
8 G
25
where H0 is the Hubble constant and G is the gravitational constant.
An estimate of H0 is 2.7 × 10–18 s–1.
(b)
(i)
Calculate a value for ρ0.
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...........................................................................................................................
...........................................................................................................................
(1)
(ii)
Hence determine the equivalent number of nucleons per unit volume at this critical
density.
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(1)
(Total 5 marks)
19.
This question is about the Big Bang model of the universe.
The graph below shows the variation with age of the universe of its temperature, based on the Big
Bang model of the universe.
10 12
10 10
10 8
temperature / K 10 6
10 4
10 2
10 0
(a)
10 0
10 2
10 4
10 6
10 8
10 10
age / s
10 12
10 14
10 16
10 18
10 20
On the graph,
(i)
mark the point (labelled N) at which light nuclei formed.
(1)
(ii)
mark the point (labelled G) at which stars and galaxies began forming.
26
(1)
(b)
Measurements of the present temperature of the universe indicate a temperature of
approximately 3 K. When taking measurements on the carbon clouds in a very distant
galaxy, the temperature indicated is 7 K. Suggest how this observation provides evidence
for the cooling of the universe.
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(2)
(Total 4 marks)
20.
One of the most intense sources known to radio astronomers is the Galaxy NGC5128. Long
exposure photographs show it to be a giant elliptical galaxy crossed by a band of dark dust. It lies
about 1.5 × 107 light years away from Earth.
(a)
Describe any differences between this galaxy and the Milky Way.
.....................................................................................................................................
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.....................................................................................................................................
(2)
Hubble’s law predicts that NGC5128 is moving away from Earth.
(b)
(i)
State Hubble’s law.
...........................................................................................................................
...........................................................................................................................
(1)
(ii)
State and explain what experimental measurements need to be taken in order to
determine the Hubble constant.
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...........................................................................................................................
........................................................................................................................... (3)
(c)
A possible value for the Hubble constant is 60 km s–1 Mpc–1. Use this value to estimate
27
(i)
the recession speed of NGC5128.
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...........................................................................................................................
...........................................................................................................................
(2)
(ii)
the age of the universe.
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(2)
(Total 10 marks)
21.
This question is about eclipsing binary stars.
(a)
In a particular binary star system, star A has apparent brightness 8.0 × 10–13 W m–2 and star
B has apparent brightness 2.0 × 10–14 W m–2.
(i)
Explain how it is possible to deduce that star A has a higher luminosity than star B.
...........................................................................................................................
...........................................................................................................................
...........................................................................................................................
(2)
(ii)
The surface area of star B is 10 000 times smaller than that of star A. Calculate the
ratio
surface temperature of star B
surface temperature of star A
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(4)
(b)
The graph below shows the variation with time of the intensity of light received on Earth
from the two stars.
28
intensity
5
(i)
10
15
time / years
The diagrams below each show the orbits of the two stars. Star A is in the inner orbit.
Annotate the diagrams to show the relative positions of stars A and B as seen from
Earth, that correspond to the intensity-time graph above at times of 5 and 10 years.
Diagram at 5 years
line of sight
from Earth
Diagram at 10 years
line of sight
from Earth
(2)
(ii)
State the period of this binary star system.
...........................................................................................................................
(1)
(iii)
State what can be deduced from knowing the period of the binary and the separation
of the stars.
...........................................................................................................................
(1)
(Total 10 marks)
29
22.
This question is about the evolution of stars.
The diagram below is a flow chart that shows the stages of evolution of a main sequence star such
as the Sun. (Mass of the Sun, the solar mass = M )
main
sequence star
mass M
(a)
red giant
nebula
planetary
dwarf
white
Complete the boxes below to show the stages of evolution of a main sequence star that has
a mass greater than 8M .
(3)
main
sequence star
mass > 8M
(b)
Outline why
(i)
white dwarf stars cannot have a greater mass than 1.4M ;
...........................................................................................................................
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...........................................................................................................................
...........................................................................................................................
(2)
(ii)
it is possible for a main sequence star with a mass equal to 8M
dwarf.
to evolve to a white
...........................................................................................................................
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(1)
(Total 6 marks)
23.
This question is about cosmic background radiation.
(a)
Describe what is meant by cosmic background radiation.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
30
(b)
The graph below shows the spectrum of the cosmic background radiation i.e. the variation,
with wavelength, of the intensity of the cosmic background radiation.
intensity
0
0
wavelength
There is evidence to suggest that the universe will expand forever. On the diagram above,
sketch a graph to show the spectrum of the background radiation for the universe many
millions of years from now.
(2)
(Total 4 marks)
24.
This question is about Hubble’s law.
The light received from many distant galaxies is red-shifted.
(a)
State the cause of this red-shift.
.....................................................................................................................................
.....................................................................................................................................
(1)
(b)
State Hubble’s law.
.....................................................................................................................................
.....................................................................................................................................
(1)
(c)
Deduce the relationship between the age of the universe T and the Hubble constant H. State
any assumptions you have made.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 4 marks)
25.
The question is about stellar radiation and the star Betelgeuse.
(a)
Explain the term black-body radiation.
31
.....................................................................................................................................
.....................................................................................................................................
(1)
The diagram below is a sketch graph of the black-body radiation spectrum of a certain star.
intensity
(b)
Label the x-axis of the graph.
(1)
(c)
On the graph, sketch the black-body radiation spectrum of a star that has a lower surface
temperature and lower apparent brightness than this star.
(2)
The star Betelgeuse in the Orion constellation emits black-body radiation that has a maximum
intensity at a wavelength of 0.97 μm.
(d)
Deduce that the surface temperature of Betelgeuse is about 3000 K.
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(1)
(Total 5 marks)
26.
This question is about extragalactic astrophysics.
(a)
In an observation of a distant galaxy, spectral lines are recorded. Spectral lines at these
wavelengths cannot be produced in the laboratory. Explain this phenomenon.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(2)
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(b)
Describe how Hubble’s law is used to determine the distance from the Earth to distant
galaxies.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(2)
(c)
Explain why Hubble’s law is not used to measure distances to nearby stars or nearby
galaxies (such as Andromeda).
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(2)
(Total 6 marks)
27.
This question is about the Hubble constant.
(a)
State the Hubble equation relating the speed v of recession of galaxies to their separation d.
...................................................................................................................................
(1)
(b)
The distance between Earth and Moon is 5.0 108 m. More precise measurement shows
that this distance is increasing at a rate of 0.04 m per year. One estimate for the Hubble
constant is 60 km s−1 Mpc−1. Using this estimate for the Hubble constant, deduce whether
the Moon’s recession can be explained on the basis of the expansion of the universe. You
may assume 1 pc = 3.1 1016 m.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(3)
(Total 4 marks)
28.
State and explain two conditions that are necessary for nuclear fusion to be initiated in a star.
1.
...................................................................................................................................
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...................................................................................................................................
2.
...................................................................................................................................
...................................................................................................................................
(Total 4 marks)
29.
This question is about cosmology.
(a)
Describe the observational evidence in support of an expanding universe.
...................................................................................................................................
...................................................................................................................................
(2)
(b)
Define the term critical density of the universe.
...................................................................................................................................
...................................................................................................................................
(1)
(c)
Discuss the significance of comparing the density of the universe to the critical density for
determining the future of the universe.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(3)
(Total 6 marks)
30.
This question is about galactic motion.
The K-line of light from singly ionized calcium has a wavelength of 393.3 nm when measured in
a laboratory. The same line in the spectrum of galaxy NGC 4889 has a wavelength of 401.8 nm.
The value of the Hubble constant may be assumed to be 70 km s–1 Mpc–1.
Deduce a value for the distance of NGC 4889 from Earth.
..............................................................................................................................................
34
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(Total 4 marks)
31.
This question is about the brightness of stars.
(a)
(i)
Define the luminosity of a star.
.........................................................................................................................
.........................................................................................................................
(1)
(ii)
State one factor that determines the luminosity of a star.
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
(1)
(b)
The graph below shows the variation with period T of the luminosity L of Cepheid variable
stars, where the luminosity of the Sun is taken to be L0.
L / L0
10 000
1000
100
10
0
(i)
5
10
15
20
T / days
Outline why the luminosity of a Cepheid star varies periodically.
35
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
(2)
(ii)
Cepheid variable star A has a period of 3.5 d; Cepheid variable star B has a period of
16.5 d. Star A is a distance of 1.6 1021 m from Earth and has an apparent brightness
at the Earth 1.2 10–14 W m–2. The apparent brightness of star B at the Earth is 5.3
10–16 W m–2.
Determine the distance of star B from the Earth.
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
.........................................................................................................................
(4)
(Total 8 marks)
32.
This question is about two different stars.
The diagram below shows the position of two main-sequence stars A and B with respect to the
labelled axes of a Hertzsprung-Russell diagram.
luminosity
(luminosity of sun = 1)
10 000
B
100
1
A
40000
20000
10000
5000
surface temperature / K
36
(a)
Suggest which of the stars has the larger mass.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(2)
(b)
State one difference between the changes in nucleosynthesis that take place in star B
compared to star A after both stars leave the main sequence.
...................................................................................................................................
...................................................................................................................................
(1)
(c)
On the diagram above, mark with the letter X, the approximate final position of star A after
it has left the main sequence.
(1)
(Total 4 marks)
33.
This question is about galaxies.
(a)
Distinguish between a galaxy and a galactic supercluster.
Galaxy:
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
Galactic supercluster:
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(3)
(b)
A galaxy is 190 Mpc from the Sun and is receding at a speed of 1.3
107 m s–1.
Use these data to determine a value for the age of the universe.
...................................................................................................................................
37
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(3)
(Total 6 marks)
34.
This question is about Olbers’ paradox.
(a)
Newton assumed that the universe is static and that the stars are uniformly distributed. State
one further assumption of the Newtonian universe.
...................................................................................................................................
...................................................................................................................................
(1)
(b)
Explain how Newton’s assumptions led to Olbers’ paradox.
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
...................................................................................................................................
(5)
(Total 6 marks)
35.
This question is about Olbers’ paradox.
Newton made three assumptions about the nature of the universe. Two of these were that the
universe is infinite and that it is static.
(a)
State Newton’s other assumption about the nature of the universe.
.....................................................................................................................................
(1)
(b)
Outline how Newton’s model of the universe leads to Olbers’ paradox.
38
.....................................................................................................................................
.....................................................................................................................................
.....................................................................................................................................
(2)
(Total 3 marks)
39