P2 - Stars Flashcards
what happens to cause the stable period in the life cycle of a star to end?
It runs out of hydrogen so nuclear fusion slows down
What will happen to the Sun after the stable period ends?
Temperature decreases and change to red giant, temperature increases and change to white dwarf
What happens to the elements produced in a supernova?
distributed through the universe
Why are stars able to give out energy for millions of years?
Hydrogen is turned to helium by nuclear fusion. Stars have a massive supply of hydrogen
Why does the Sun remain stable for millions of years?
Inward force of gravity is equal to the outward force of radiation pressure for millions of years
How did the elements some to be formed?
Nuclear fusion of hydrogen forms helium; heavy elements are formed by the fusion of lighter elements during a supernova
Describe how a star forms.
Dust and gas is pulled together by gravity
What happens to massive stars after the red super giant stage?
Outer layers are thrown into space which scatters gas and dust into space and distributes the elements throughout space. The core left behind forms a neutron star or black hole if sufficient mass is left behind
Why do scientists believe the Solar System was formed from the material produced when earlier stars exploded?
Solar System contains elements heavier than hydrogen and helium which were formed by nuclear fusion in a supernova
What is a black hole?
matter with such high density that light is pulled in
What is produced as the gases from a star spiral into a black hole?
X rays
Why are fusion reactors not used to generate electricity?
They currently are only experimental and use more energy than they release
Why do scientists continue to try and develops nuclear fusion power plants?
provide unlimited energy, no radioactive waste produced, want to show that it can be done
