Astronomy final

The center of gravity of the Solar System is located at the center of the Sun.

• True

• False

Most elements present on the periodic table are produced by stars, either in cores or by stellar explosions.

• True

• False

Each time a high mass star runs out of a heavier element to fuse, it fuses heavier elements more rapidly in the core due to the large increase in temperature.

• True

• False

A nearby star's spectrum reveals that its peak wavelength is 300 nm, placing most of its emitted photons in the ultraviolet. Therefore, I can conclude that this star is hotter than the Sun.

• True

• False

Red is a higher temperature color than blue.

• True

• False

The evolution of a low mass star can be described by which of the following sequences on an HR Diagram?

• Main Sequence → Red Giant → Planetary Nebula → White Dwarf

• Main Sequence → Supergiant → Black Hole

• Main Sequence → Neutron Star → Supernova

• Main Sequence → Brown Dwarf → Black Dwarf

If the temperature of the core of the Sun increased, what would happen to nuclear reactions, radiation pressure, and the Sun's contraction or expansion?

• Nuclear reactions would speed up, radiation pressure would increase, and the Sun would expand.

• Nuclear reactions would slow down, radiation pressure would decrease, and the Sun would contract.

• Nuclear reactions would stop, radiation pressure would remain the same, and the Sun would collapse.

• Nuclear reactions would speed up, radiation pressure would decrease, and the Sun would contract.

The structure of the Sun includes several layers, each with a different method of energy transport towards the surface. Which of the following best describes how energy is transported in each substructure of the Sun?

• Energy is transported by radiation in the core and radiative zone, and by convection in the convective zone.

• Energy is transported by convection in the core and radiative zone, and by radiation in the convective zone.

• Energy is transported by conduction in all layers of the Sun.

• Energy is transported by radiation in the convective zone and by convection in the core and radiative zone.

The absorption spectrum of a star tells us about its chemical composition and temperature by:

• showing which wavelengths of light are absorbed by elements in the star's atmosphere

• measuring the star's brightness only

• indicating the star's distance from Earth

• showing the star's movement through space

Which of the following correctly describes the three types of spectra and how each is produced?

• Continuous spectrum: produced by a hot, dense object; Emission spectrum: produced by a hot, low-density gas; Absorption spectrum: produced when light passes through a cooler gas.

• Continuous spectrum: produced by a cold, dense object; Emission spectrum: produced by a solid; Absorption spectrum: produced by a hot, dense object.

• Continuous spectrum: produced by a hot, low-density gas; Emission spectrum: produced by a hot, dense object; Absorption spectrum: produced by a solid.

• Continuous spectrum: produced by a cooler gas; Emission spectrum: produced by a cold, dense object; Absorption spectrum: produced by a hot, low-density gas.