a. It is dying
d. Its mass is greater than 20 times that of the sun
Which of these characteristics of a star make it most likely to become a black hole? Select two correct answers.
a. It is dying
b. Its mass is equal to that of the sun
c. It has an abundant supply of hydrogen
d. Its mass is greater than 20 times that of the sun
9 answers
Which statement best describes the galaxies closest to the Milky Way?
a. These galaxies consist of mostly old stars
b. These galaxies are independent of and unaffected by the Milky Way's gravitational pull
c. These galaxies are all identified as spiral
d. These galaxies include irregular, spiral, and elliptical galaxies
a. These galaxies consist of mostly old stars
b. These galaxies are independent of and unaffected by the Milky Way's gravitational pull
c. These galaxies are all identified as spiral
d. These galaxies include irregular, spiral, and elliptical galaxies
d. These galaxies include irregular, spiral, and elliptical galaxies
Which description best summarizes the steps that take place during black hole formation, in the correct order?
a. A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses
b. A small star gains mass through fusion reactions; core of star collapses; increased radiation triggers supernova
c. Supernova triggers fusion reactions; massive star implodes due to extreme radiation; volume and mass of star increase rapidly
d. Supernova explodes a massive star; remaining core expands; nuclear reactions diminish the effects of gravity
a. A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses
b. A small star gains mass through fusion reactions; core of star collapses; increased radiation triggers supernova
c. Supernova triggers fusion reactions; massive star implodes due to extreme radiation; volume and mass of star increase rapidly
d. Supernova explodes a massive star; remaining core expands; nuclear reactions diminish the effects of gravity
a. A massive star depletes its nuclear fuel; gravity overpowers the star; supernova occurs; core of star collapses
How do emission and reflection nebulae differ?
a. the presence of young stars
b. contain remnants of stars
c. hard line edges
d. interactions with light
a. the presence of young stars
b. contain remnants of stars
c. hard line edges
d. interactions with light
a. the presence of young stars
are you sure?
I apologize for the incorrect response. Let me correct myself.
Emission and reflection nebulae differ in terms of their interactions with light.
Emission nebulae are made up of gas that emits its own light due to the presence of ionized atoms and molecules. These nebulae are often associated with regions of star formation and contain young, hot stars that emit ultraviolet radiation, which in turn excite the surrounding gas to emit light.
On the other hand, reflection nebulae do not emit their own light. Instead, they reflect the light from nearby stars or star clusters. The dust in the reflection nebula scatters and reflects the starlight, giving them a bluish appearance.
So the correct answer is:
d. interactions with light
Emission and reflection nebulae differ in terms of their interactions with light.
Emission nebulae are made up of gas that emits its own light due to the presence of ionized atoms and molecules. These nebulae are often associated with regions of star formation and contain young, hot stars that emit ultraviolet radiation, which in turn excite the surrounding gas to emit light.
On the other hand, reflection nebulae do not emit their own light. Instead, they reflect the light from nearby stars or star clusters. The dust in the reflection nebula scatters and reflects the starlight, giving them a bluish appearance.
So the correct answer is:
d. interactions with light