Popquiz

1
Pop-quiz 31

• Which of the following statements is FALSE?
• When a star finishes burning all the hydrogen in
  its core, it ceases to be a main sequence star
• The helium flash (ignition of the helium core)
  takes place at the tip of the red giant branch
• A planetary nebula is formed when a star loses
  part of its outer envelope in a stellar wind and
  this is the material from which planets are
  formed
• The Zero Age Main Sequence represents the locus
  of points on the HR diagram where nuclear fusion
  starts

2
Pop-quiz 32

• Which of the following statements is TRUE?
• The constancy of the speed of light is a basic
  principle of the Special Theory of Relativity
• The General Theory of Relativity was designed to
  explain situations where the speeds of objects
  are close to the speed of light
• The Special Theory of Relativity states that a
  moving ruler is measured to be longer than its
  twin ruler at rest
• The mass or inertia of an object decreases when
  its speed approaches the speed of light

3
Pop-quiz 33

• Which of the following statements is FALSE?
• Stars in the disk of a spiral galaxy tend to be
  younger than those in the bulge
• Observations of globular clusters in the Milky
  Way led Shapley to conclude that the Sun is not
  located at our Galaxys center
• Most galaxies are thought to have massive black
  holes at their centers
• Stars in an elliptical galaxy move in a coherent
  fashion about the galaxys center