Astrophysics

What is luminosity in terms of a star?

• Total power of radiation emitted by a star

• Distance between stars

• Surface temperature of a star

• Mass of a star

What is the radiant flux intensity?

• Distance between stars

• Power passing through a surface per unit area

• Temperature of a star

• Brightness of a star

What is the purpose of standard candles in astronomy?

• Study the composition of stars

• Determine distances to galaxies

• Measure the size of stars

• Classify stars based on color

What is the relationship between luminosity and distance from a source?

• Radiant flux decreases by a factor of 2 when distance is doubled

• Radiant flux remains constant with distance

• Radiant flux increases when distance is doubled

• Radiant flux decreases by a factor of 4 when distance is doubled

What is the Stefan-Boltzmann law used for?

• Calculate the distance between stars

• Determine the color of a star

• Measure the brightness of a star

• Estimate the luminosity of a star based on its temperature and radius

What does redshift in the spectra of distant galaxies indicate?

• Galaxies are moving away from us

• Galaxies are rotating

• Galaxies are moving towards us

• Galaxies are stationary

What did Edwin Hubble discover about the movement of galaxies?

• Galaxies do not move

• Further galaxies move faster away from us

• Closer galaxies move faster away from us

• All galaxies move at the same speed

What is the Big Bang theory?

• Model of creation of the universe from a hot and dense state

• Model of a static universe

• Model of a contracting universe

• Model of a flat universe