Our Evolving Universe
Self Test 3

1. The Hertzspring-Russell diagram is a plot of luminosity against temperature (on a logarithmic scale). On the horizontal axis, you could plot
   1. spectral class (OBAFGKM)
   2. colour (from blue to red)
   3. either (a) or (b)
   4. neither (a) nor (b): you must plot temperature
   
   
2. A star near the top right-hand corner of the HR diagram is
   1. bright and hot
   2. bright and cool
   3. faint and cool
   4. faint and hot
   
   
3. Compared to a star at bottom right, our star at top right must be
   1. closer to us
   2. further away from us
   3. smaller
   4. larger
   
   
4. The size of a star is determined by
   1. its mass: the density of stellar material is known from the Sun
   2. its surface temperature: larger stars are always hotter
   3. the balance between pressure and gravity
   4. none of the above
   
   
5. Compared to the Sun, a star ten times as massive would stay on the main sequence for
   1. longer, as it has more fuel
   2. less time, as it is much brighter
   3. about the same time, because the extra fuel cancels out the extra brightness
   4. either longer or less long, depending on its temperature

out of 5.

Go back to Summary of Lecture 3
Go on to Summary of Lecture 4
Go back to main page