Exploring the Cosmos - Class Test 3 - Life and Death of Stars (Part 2)
1. The Crab Nebula is of interest because it
contains a pulsar.
is in the centre of the constellation Cancer.
surrounds the supernova SN1987A.
contains a black hole.
2. A globular cluster in our Galaxy is
an asterism like the Pleiades.
a group of very young stars.
a group of very old stars.
a constellation such as Orion.
3. Type I and II supernovae
are both standard candles.
will occur in stars less massive than the Sun.
will occur in stars more massive than the Sun.
can reoccur.
4. The main sequence is
OBAFGKMRN.
a line on a graph of luminosity against temperature.
the succession of stages in the life of a star.
a nuclear reaction in very hot stars.
5. An open cluster in our Galaxy is
most likely to be found in the galactic halo.
a group of newly formed stars.
a group like the Pleiades.
a constellation such as Orion.
6. White dwarfs
are very hot.
are the remains of stars much less massive than the Sun.
are low magnitude stars.
are very small in number.
7. Hydrogen burning in stars
is a reaction in which hydrogen fuses with oxygen.
is a nuclear reaction only occurring in the hottest stars.
can occur in the proton-proton chain reaction.
produces water vapour in interstellar space.
8. One element not expected to be produced in the core of stars is
silicon.
helium.
gold.
carbon.
9. Gas clouds contract to form stars because of
electrical attraction.
nuclear forces.
internal pressure.
gravity.
10. Stars in a single cluster differ widely in
chemical composition.
distance.
age.
mass.
11. Which of the following elements is not expected to be common in the core of a white dwarf?
Oxygen
Carbon
Hydrogen
Silicon
12. The CNO cycle is a nuclear reaction which
causes the helium flash.
occurs in stars with cores hotter than the Sun.
produces 'metals'.
occurs in carbon white dwarfs.
13. The final state of a star depends mainly on its
degeneracy.
mass.
chemical composition.
magnitude.
14. T Tauri stars are
frequently strong infrared sources.
remnant cores of dead stars.
standard candles.
optically visible in their cocoon.
15. Given that the radius of the Sun is about 700,000 km
it takes a few hours for light to travel from the core to the photosphere.
energy from fusion takes about 1 million years to travel this distance.
energy from fusion appears almost instantly at the photosphere.
light takes 2 to 3 seconds to travel from the core to the photosphere.
16. Protostars heat up mostly due to
gravitational contraction.
nuclear fission.
radioactivity.
nuclear fusion.
17. If 4 hydrogen nuclei fuse to form a helium nucleus
the mass drops by about 1%.
the mass-energy increases by about 1%.
the mass is conserved.
energy is absorbed.
18. The Chandrasekhar limit is
the maximum radius of a red giant.
the radius of a black hole.
around ten times the solar mass.
the maximum mass of a white dwarf.
19. Type I and II supernovae
will occur in stars more massive than the Sun.
are both standard candles.
will occur in stars less massive than the Sun.
can reoccur.
20. Type Ia supernovae are
are thought to be exploding white dwarfs.
have strong H lines.
very bright, newly-formed stars.
caused by stars collapsing upon themselves.
21. When the Sun becomes a Red Giant
its surface will become hotter than it is now.
it will eventually become a supernova.
it will produce iron and heavier elements in its core.
hydrogen fusion in its core will have ceased.
22. Which of the following elements is not expected to be common in the core of a white dwarf?
Carbon
Silicon
Oxygen
Hydrogen
23. The triple-alpha reaction is
a nuclear reaction in which helium fuses to form carbon.
an intermediate stage in the Carbon-Oxygen-Nitrogen cycle.
an intermediate stage in the proton-proton chain reaction.
responsible for the formation of globular clusters.
24. The supernova SN1987A
was at the same position as a previously catalogued star.
emitted gravitational radiation which was detected on Earth.
is the most distant supernova seen until now.
was seen in the nearby Andromeda galaxy.
25. One element not expected to be produced in the core of stars is
silicon.
gold.
carbon.
helium.
26. The supernova SN1987A
emitted gravitational radiation which was detected on Earth.
was at the same position as a previously catalogued star.
was seen in the nearby Andromeda galaxy.
is the most distant supernova seen until now.
27. The Chandrasekhar limit is
the radius of a black hole.
the maximum mass of a white dwarf.
the maximum radius of a red giant.
around ten times the solar mass.
28. Black holes
are caused absorption of light in cold, dense nebulae.
are detected as dark clouds at the centre of galaxies.
are the final stages of stars like the Sun.
cannot be directly observed.
29. The Schwarzschild radius gives
the size of a neutron star.
the radius of the observable Universe.
the size of a black hole.
the maximum size of a white dwarf.
30. Type I and II supernovae
can reoccur.
will occur in stars less massive than the Sun.
are both standard candles.
will occur in stars more massive than the Sun.
31. The Pauli Exclusion Principle explains
why white dwarfs are stable.
supernovae.
why neutron stars collapse.
the solar neutrino problem.
32. The final state of a star depends mainly on its
chemical composition.
magnitude.
mass.
degeneracy.
33. One element not expected to be produced in the core of stars is
carbon.
helium.
gold.
silicon.
34. The position of white dwarfs on a HR diagram is
to the right of the main sequence.
on the upper part of the main sequence.
to the lower left of the main sequence.
at random points on the diagram.
35. When the Sun becomes a Red Giant
hydrogen fusion in its core will have ceased.
it will eventually become a supernova.
its surface will become hotter than it is now.
it will produce iron and heavier elements in its core.
36. The CNO cycle is a nuclear reaction which
causes the helium flash.
produces 'metals'.
occurs in carbon white dwarfs.
occurs in stars with cores hotter than the Sun.
37. Black holes
can only exist at the centres of galaxies.
are also called accretion disks.
are massive neutron stars.
exert a strong gravitational pull.
Submit Quiz