8.9A Mastery Bell Ringer

A scientist observes a red giant star and predicts its future. Which is the most reasonable explanation for what will happen next?

• It will become a protostar again

• It will collapse into a white dwarf

• It will explode into a supernova and become a black hole

• It will turn into a blue supergiant

Based on the Hertzsprung-Russell diagram, which characteristic do stars on the main sequence share?

• High luminosity and low temperature

• Low mass and irregular shapes

• A relationship where hotter stars are more luminous

• All stars on the main sequence are red dwarfs

A student compares two stars: Star X is very bright and blue-white; Star Y is dim and red. Based on the H-R diagram, which conclusion is most likely correct?

• Star X is older and cooler than Star Y

• Star X is hotter and likely has more mass than Star Y

• Star Y is on the main sequence and Star X is a white dwarf

• Both stars have similar surface temperatures

A massive star ends its life in a supernova. What are two possible outcomes depending on its remaining mass?

• Protostar or red giant

• Main sequence or red dwarf

• Neutron star or black hole

• White dwarf or supergiant

Which sequence best describes the life cycle of a star with similar mass to the Sun?

• Nebula → Main Sequence → Red Giant → White Dwarf

• Nebula → Supernova → Neutron Star → Black Hole

• Main Sequence → White Dwarf → Protostar → Red Giant

• White Dwarf → Red Giant → Nebula → Main Sequence

Tags

NGSS.HS-ESS1-3

Which of the following best explains why blue stars are found in the upper left of the H-R diagram?

• They are cooler and older

• They are cooler and less bright

• They are hotter and more luminous

• They are less massive but still young

A scientist finds a star that is cool but extremely bright. Based on this information, the star is most likely a —

• white dwarf

• red giant

• main sequence star

• protostar

Why does a high-mass star have a shorter lifespan than a low-mass star?

• It burns fuel more slowly and cools faster

• It collapses into a nebula earlier in life

• It uses up its fuel more quickly due to stronger gravity

• It spends more time as a red giant

Tags

NGSS.HS-ESS1-3

Two students debate the fate of stars. Student A says all stars end as black holes. Student B says only some do. Who is correct and why?

• Student A, because black holes are the final stage for all stars

• Student B, because only the most massive stars become black holes

• Student A, because stars turn into black holes after the red giant phase

• Student B, because all stars become supernovae first

A star moves off the main sequence and becomes a red giant. What does this suggest about changes in the star’s core?

• The core is expanding due to increased hydrogen

• The core is shrinking and heating as helium fusion begins

• The core cools down and starts forming planets

• The core stops nuclear fusion and solidifies completely

Tags

NGSS.HS-ESS1-3