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
a. It is dying
d. Its mass is greater than 20 times that of the sun
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
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
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
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
To determine which characteristics of a star make it most likely to become a black hole, let's analyze the options given:
a. It is dying: This characteristic alone does not determine if a star is likely to become a black hole. The type of death, such as a supernova, can lead to a black hole, but there are other factors to consider as well.
b. Its mass is equal to that of the sun: Stars with the mass of the sun do not typically become black holes. They usually end their life as white dwarfs or neutron stars.
c. It has an abundant supply of hydrogen: While the abundance of hydrogen is crucial for nuclear reactions in stars, it does not determine if a star will become a black hole.
d. Its mass is greater than 20 times that of the sun: This is one correct characteristic. Stars that have a mass more than 20 times that of the sun have the potential to become black holes. This is because they have enough mass to undergo a supernova explosion and leave behind a remnant that can collapse into a black hole.
Based on the options provided, the correct characteristics that make a star most likely to become a black hole are:
1. Its mass is greater than 20 times that of the sun.
2. It is dying (specifically through the process of a supernova).
Therefore, the correct answers are options d and a.