Third Edition Refuel the Reactor Palen - Understanding Our Universe 3e Complete Test Bank by Stacy Palen. DOCX document preview.
Mission 5: Refuel the Reactor
MULTIPLE CHOICE
1. Which of the following accurately describes changes to a star when it first moves off the main sequence of the HR diagram?
a. increased radius and increased surface temperature
b. increased radius and decreased surface temperature
c. shorter wavelength of peak radiation
d. absence of nuclear fusion
e. decreased luminosity
2. Which of the following particles is not involved or produced in the proton-proton chain reactions for fusion?
a. proton d. deuteron
b. carbon e. helium-3
c. positron (positively charged electron)
3. Red Giant stars have inert (i.e., not fusing) cores made of
a. oxygen. d. beryllium.
b. nitrogen. e. helium.
c. carbon.
4. Given that red giant stars are more luminous than they were when they were main-sequence stars fusing hydrogen in their cores, which of the following statements is not true?
a. The hydrogen-burning layer in a red giant star produces more energy than the hydrogen-burning core produced when the star was a main-sequence star.
b. A red giant star is cooler, but its radius increases so much that it is more luminous at this stage than it was when it was a hotter, main-sequence star.
c. The rate at which a red giant loses mass in a solar-like stellar wind is far greater than its mass loss rate when it was a more compact, main-sequence star.
d. The contraction of the core leads to a lower fusion temperature for the hydrogen-burning layer and higher fusion rates.
5. Arcturus, a red giant, has a radius of 3.8 × 109 km. Approximately how many times larger than the Sun is Arcturus?
a. 2.5 d. 2,500
b. 25 e. 25,000
c. 250
1. Red giant stars experience significant mass loss through the strong winds depicted in the mission. What about their size helps to explain why these stars have such strong winds?
2. If the helium-3 is being produced in an extremely hot layer of hydrogen surrounding a non-fusing helium-4-dominated core, how does this helium-3 make it to the surface and eventually into the stellar wind?