Read Chapter 14
2.)
Consider an object, for example, a cloud of gas,
that is quickly contracting due to gravity's inward pull.
a.) Is it in hydrostatic equilibrium?
b.) Why or why not?
3.)
a.) If you can see through the chromosphere and the corona, then
they must be: (pick one)
optically thin or optically thick
b.) If you cannot see through the convection zone or radiation zone, then
they must be: (pick one)
optically thin or optically thick
4.) How does the convection zone compare with the radiative zone in terms of a.) Temperature b.) Pressure c.) Gas motion
5.) The part of the Sun where mass is converted into energy is
the:
a.) Chromosphere
b.) Convection zone
c.) Core
d.) Corona
e.) None of the above
6.)
a.) Where is the Sun's chromosphere?
b.) Where is the Sun's convection zone?
c.) Where is the Sun's core?
d.) Where is the Sun's corona?
e.) Where is the Sun's photosphere?
f.) Where is the Sun's radiation zone?
7.) What are the steps in the nuclear reactions that convert
hydrogen into helium + gamma rays + positrons + neutrinos + kinetic energy?
8.)
Every second, 4 x 109 kg of mass is converted into
energy in the Sun.
Use E = m c2 to calculate the amount of energy per second
produced by the Sun as a result.
9.) Use several sentences to describe:
a.) the process of
radiative diffusion in the core and radiation zone and
b.) the process of convection in the convection zone.
10.) (adapted from textbook) Which one of the following choices is sensible and true? a.) A sudden temperature rise in the Sun's core is nothing to worry about because conditions in the core will soon return to normal. b.) If fusion in the solar core ceased today, worldwide panic would break out tomorrow as the Sun began to grow dimmer. c.) Astronomers have recently photographed magnetic fields churning deep beneath the solar photosphere. d.) Neutrinos probably can't harm me, but just to be safe I think I'll wear a lead vest. e.) By observing solar neutrinos, we can learn about motion in the Sun's convection layer.
11.) (adapted from textbook)
During its life, the Sun will burn up the hydrogen in
the core to produce energy, helium, and other particles.
During its lifespan (i.e. starting from birth),
the Sun will burn 1.95 x 1029 kg of hydrogen in its core.
The Sun burns 600 billion kg (that is 600 x 109 kg)
of hydrogen every second. If the burn rate were to be constant,
how long would it take for the Sun to burn through the hydrogen
in its core? Note that this is the total lifetime, starting
from the time of the Sun's birth, not starting from now.
Please provide your final answer in units of years.
12.) The hydrogen outside the core doesn't burn. Why not?
13.) Write a several-sentence long description of the
magnetic fields on the Sun's surface,
including how they are affected by the convection layer,
what they do to electrons and ions, and their role in making sunspots.
14.)
a.) Do neutrinos interact easily with atoms?
b.) How do we detect some of the neutrinos made by the Sun?
15.) What would happen to the core of the Sun if the fusion rate were to momentarily and suddenly increase by 10%? (For your answer, consider how the fusion rate affects the production of energy, how the production of energy affects the temperature of the gas, how the temperature affects the pressure, how a change in pressure affects the size of the core, how a change in the size of the core affects the temperature, and how the temperature of the core affects the fusion rate)