Chapter 11 part 1 Flashcards
What is the source of the sun’s power?
Fusion of hydrogen into helium
Nuclear Fusion
Formula for converting mass into energy
E = mc^2
What creates a Helium nucleus?
4 Hydrogen Nuclei
Why does nuclear fusion create energy?
Because the 4 Hydrogen Nuclei have a slightly higher mass than a Helium nucleus , the difference in mass is turned into energy
What would happen to the Sun if fusion produced more energythan the Sun was able to radiate from its surface?
The amount of energy inside the Sun would increase
Sun’s structure
Solar Wind > Corona > Chromosome > Photosphere (sunspots) > Convection Zone > Radiation Zone > Core
What proof is there for the Sun
Mathematical Models ,
Solar Vibrations ,
Neutrino Observations
What is the source of solar activity?
Magnetic Fields
What keeps the Sun hot?
Nuclear Fusion in the Sun’s core
What is the Sun made up of?
Hydrogen and Helium
What does the Sun’s Photosphere do?
Radiate energy into space
What does the Sun’s Radiation and Convective zones do?
Transport energy to the Photosphere by slow diffusion of photons. Since the photons are interacting with gas, their energy (and frequency) is proportional to that of the gas.
How does thermal energy flow?
From hotter regions to cooler regions
What is the rough temp of the Sun’s center?
15 Million Kelvin
Nuclear Fusion of Hydrogen doesn’t happen at temperatures lower than what?
About 10 Million Kelvin
What happens to the energy of the photons as it goes away from the core and to the photosphere?
The gas gets cooler, so the energy gets lower.
What is the main difference between stars and planets?
Nuclear Fusion occurs in stars .
What is Nuclear Fusion?
Two or more nuclei stick together or fuse, forming a larger nucleus.
The Sun will exhaust its nuclear fuel in about ______.
5 billion years
What type of radiation is most prevalent in the radiation zone
X Rays
How do we estimate the life span of the sun?
By determining how long it will take for all the hydrogen initially in the core to be fused into helium. The core began with roughly the same composition as the universe as a whole: about 75% hydrogen and 25% helium.
(10^10 Years)
If the sun had the same mass but a lower luminosity, its lifespan would be
Longer than 10 billion years
How does the force depend on distance?
It increases as the distance decreases
Radar Method
Send radio waves and measure how long it takes the waves to hit a planet and come back
