Unit 4 Test Review Chapter 25- Stars and the Universe

What color will a star be with a temperature of of 5000-6000 K?

• blue

• red

• yellow

• white

What feature of stars are binary stars useful for determining?

• wavelength

• color

• distance

• mass

What is parallax, and what is true of the parallax angle of closer stars?

• the closer the star, the smaller is the parallax angle

• the closer the star, the larger is the parallax angle

• the larger the star, the smaller is the parallax angle

• the larger the star, the larger is the parallax angle

How long is a light year in kilometers?

• 9.5 billion km

• 95 billion km

• 9.5 trillion km

• 95 trilliion km

Which is NOT a factor that affects the apparent brightness of a star as seen from Earth?

• how old the star is

• how big the star is

• how hot the star is

• how far away the star is

Star A is farther from Earth than star B. Both stars have the same absolute magnitude. Which of the following is true about their apparent magnitude?

• both stars will have the same apparent magnitude

• Star A will have a greater apparent magnitude

• Star B will have a greater apparent magnitude

• The apparent magnitude of either star will not depend on its positioin

What relationship does the Hertzsprung-Russell diagram show?

• absolute magnitude and apparent magnitude

• temperature and absolute magnitude

• parallax and temperature

• apparent magnitude and parallax

What percentage of stars on the Hertzsprung-Russell diagram are main sequence stars?

• 10%

• 25%

• 75%

• 90%

What are stars made from originally?

• a bright explosive supernova

• red giant

• black hole

• cool, dark nebula

When does a protostar actually become a star?

• when it reaches a temperature high enough for nuclear fusion to begin

• when a red giant collapses on itself

• when pressure within a protostar becomes so great that a supernova occurs

• when heat within a supergiant cause gravity to be greater than pressure