Choose only one answer for each question
1. What is the central temperature of the sun?
a. 3000 Kelvin
b. 6000 Kelvin
c. 15 million Kelvin
d. 1 billion Kelvin
2. Where in the sun does nuclear fusion take place?
a. in the core
b. in a shell surrounding the core
c. in the convective zone
d. in the atmosphere
3. Why do we study solar oscillations (helioseismology)?
a. It allows us to predict when solar flares will erupt
b. It allows us to probe the temperature, density, and composition of
the sun below the photosphere
c. It allows us to map the surface magnetic field of the sun
d. It allows us to measure the number of neutrinos being emitted by the sun
4. Why do neutrinos let us see into the core of the sun?
a. they are easy to detect
b. they don't interact with the material outside the sun's core
c. they interact only with material on earth, not with solar material
d. they bounce around inside the sun, getting more information with each
pass through the core
5. What prevents gravity from making a Main Sequence star collapse into an
infinitely dense point?
a. centrifugal force balances the force of gravity
b. the strong nuclear force balances the force of gravity
c. gas pressure balances the force of gravity
d. electron degeneracy, or the fact that more than one electron cannot be
in the same quantum state, prevents the star from collapsing
6. A 10 solar-mass star is 40,000 times as luminous as the sun. If the
sun has a lifetime of 10 billion years, what is the lifetime of the 10
solar-mass star?
a. 2.5 million years
b. 1 billion years
c. 10 billion years
d. 100 billion years