Chapter 16 Flashcards
The sun is a what?
A garden variety star
The suns energy output is what?
4x10^26 watts
Watts is a unit of what?
power
What do watts tell us?
the rate at which energy is being used
How to get joules?
weight x speed = joules
100 watts = ?joules
100 joules
How does the sun put out its energy?
The the law of conservation of energy
what is the law of conservation of energy?
energy can not be created or destroyed but can be transferred from one type to another
eisteinswhat did listens theory of relativity state?
that matter can be considered a form of energy too and can be converted into energy
what is the equation for converting mass to energy?
E=mc^2
E=energy
m=mass
c^2=(3x10^8)^2
the conversion of mass into energy is the suns source of what?
heat and light
the sun is a big reserve of what?
matter
all stars produce their energy through what?
nuclear fusion
what is nuclear fusion?
the joining together of nuclei
atomic nuclei contain what?
positively charged protons
because nuclei contain positively charged protons they naturally do what?
repel each other
how to we overcome the repulsion of the protons?
heat; the particles start moving faster
two protons can fuse together in regions hotter than what?
12 million k
what is the 3 step process called in the sun?
the proton-proton chain
what happens in the proton-proton chain?
4 nuclei combine to create helium nucleus. the nucleus has less mass than the four nuclei combined and the mass lost is converted into energy.
when what is converted into what in the proton-proton chain, how much of what’s mass is converted into energy?
hydrogen, helium, hydrogen, 0.071%,
the sun is what? which means its neither what or what?
stable, expanding, contracting
hydrostatic equilibrium is when what?
when the pressure inside the star is greater than the outside force causing it to expand. once it expands as far as it can go, it balances back out into equilibrium.
