CH 30 Stars Galaxies, and the Universe

What color are the coolest stars?

• red
• orange
• white
• blue

Stars appear to move in the sky because

• Earth is moving.
• the sky is rotating.
• the universe is expanding.
• galaxies are forming.

A star that is moving away from Earth has a spectrum that is

• shifted toward red.
• losing its color.
• shifted toward blue.
• unchanged.

Tags

NGSS.HS-ESS1-2

Scientists determine the composition and temperature of stars

• by analyzing the spectra of the light that stars emit.
• by sampling matter on the surface of stars.
• by analyzing the vibrations that stars emit.
• through magnetic testing.

Tags

NGSS.HS-ESS1-2

A small, hot, extremely dense core left after a star collapses is a

• white dwarf.
• black dwarf.
• red giant.
• red dwarf.

During the main sequence stage, how is energy generated in a star’s core?

• Hydrogen fuses into helium.
• Carbon fuses into hydrogen.
• Helium fuses into hydrogen.
• Carbon fuses into oxygen.

Tags

NGSS.HS-ESS1-1

How long would a star with the sun’s mass stay on the main sequence?

• 10 billion years
• a million years
• a billion years
• 10 trillion years

Tags

NGSS.HS-ESS1-1

After its temperature rises to 10,000,000 °C, a protostar becomes a star when

• nuclear fusion begins.
• nuclear fusion ends.
• nuclear fission begins.
• nuclear fission ends.

Tags

NGSS.HS-ESS1-1

NGSS.HS-PS1-8

A large, bright star whose hot core has used most of its hydrogen is a

• giant.
• pulsar.
• nova.
• supernova.

Tags

NGSS.HS-ESS1-1

NGSS.HS-ESS1-3

What are binary stars?

• pairs of revolving stars held together by gravity
• stars like the sun and Earth
• pairs of stars held motionless by gravity
• stars with two poles