Many massive stars end their life cycles as black holes. Why do astronomers not believe the sun will end its life cycle as a black hole? (1 point)
Responses
It is not at the center of the solar system.
It is not at the center of the solar system.
It is not a binary star.
It is not a binary star.
It is not massive enough.
It is not massive enough.
It is much too hot.
It is much too hot.
The sun is composed primarily of which two elements?(1 point)
Responses
Hydrogen and Helium
Hydrogen and Helium
Oxygen and Carbon
Oxygen and Carbon
Carbon and Nitrogen
Carbon and Nitrogen
Iron and Silicon
Hydrogen and Helium
Which process generates the sun's energy?(1 point)
Responses
Nuclear fusion
Nuclear fusion
Nuclear fission
Nuclear fission
Combustion
Combustion
Photosynthesis
Nuclear fusion
Which is a correct statement about Aristotle's and Ptolemy's models of the solar system?(1 point)
Responses
Ptolemy's model involved epicycles moving along perfect circles.
Ptolemy's model involved epicycles moving along perfect circles.
Aristotle's model involved epicycles moving within crystalline spheres.
Aristotle's model involved epicycles moving within crystalline spheres.
Aristotle's model put the Sun at the center.
Aristotle's model put the Sun at the center.
Ptolemy's model was very useful because it was correct.
Ptolemy's model involved epicycles moving along perfect circles.
According to Kepler’s second law, which factor is constant as a line between a planet and the sun sweeps out two equal areas at different places as it moves along its orbit?(1 point)
Responses
the distance the planet moves
the distance the planet moves
the amount of time
the amount of time
the planet’s speed
the planet’s speed
the distance from the sun to the planet
the amount of time
The mass of an object decreases by one-half. What happens to the gravitational force between the object and a second object whose mass stays the same? (1 point)
Responses
The gravitational force decreases to one-fourth.
The gravitational force decreases to one-fourth.
The gravitational force stays the same, as long as the objects remain on Earth.
The gravitational force stays the same, as long as the objects remain on Earth.
The gravitational force decreases by one-half.
The gravitational force decreases by one-half.
The gravitational force doubles.
The gravitational force doubles.