1. true or false? a hertzsprung-russell (h-r) diagram is a convenient way to see the relationship between the luminosity and the brightness of stars.

2. convert the following temperatures.
a. b. c.
3. on an a.
b. c. d.
kelvin = 100 ocelsius 0 kelvin = ocelsius 273 kelvin = ocelsius
h-r diagram,
luminosity decreases from bottom to top.
temperature increases from left to right.
temperature decreases from left to right.
absolute magnitude increases from top to bottom.
4. what does a single dot on an h-r diagram represent?
5. which statement describes how a star moves within an h-r diagram?
a. a star never moves once its position is established on the diagram.
b. a star always stays in one region its entire existence.
c. a star migrates from one region to another as it goes through different stages.
d. all stars start in the upper left corner and travel through each region until they reach the bottom right corner.

6. on the h-r diagram above, identify the types of stars in the regions next to the lines 6a and 6b.
7. on the h-r diagram above, identify the general location of our sun and label it.
8. how can you use the h-r diagram to find out if a giant star could have the same temperature as a red giant star?
9. a star’s spectral class is most dependent on
a. its size and shape.
b. its color and temperature.
c. its luminosity and gravity.
d. its age and size.

10. the star rigel in the constellation orion has an absolute magnitude of 0.18 and is about 250 parsecs away. what is its apparent magnitude? does it look brighter or dimmer than the star vega to us? vega’s apparent magnitude is 0.04.