Session 10: Writing Exercise

FILL IN THE BLANKS:

1. A white dwarf is kept from collapsing by the incompressability of its ________. A similar role is played by the ________ in a neutron star.

2. The radius of a white dwarf is about ________ miles; the radius of a neutron star is more like ________ miles.

3. A star which is much more massive than the sun could probably end up as a(n) ________. Such an object would be distinguished by its high mass and copious emission of ________.

4. It is probable that ________ are rapidly ________ neutron stars.

MULTIPLE CHOICE QUESTIONS:

5. Physics predicts that
   (a) matter or energy can never enter a black hole.
   (b) nothing can stop the collapse of a black hole.
   (c) black holes will "pop out" of our Universe and be undectable by any means.
   (d) pulsars are black holes.

6. The size of pulsars has been estimated primarily by their
   (a) low luminosity.
   (b) distance.
   (c) location on the galactic plane.
   (d) rapid variability.

7. Pulsars typically fluctuate in brightness over a period of
   (a) 1/10 second.
   (b) 10 seconds.
   (c) 10 minutes
   (d) several hours.

8. The following are ordered correctly with increasing size:
   (a) Neutron star, black hole, white dwarf, sun, red giant.
   (b) Black hole, neutron star, white dwarf, sun, red giant
   (c) Neutron star, black hole, sun, white dwarf, red giant.
   99

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