13. Why does the Solar System rotate? * (1 Point) The planets exert gravitational forces on each other. As the Solar Sys

Post by **answerhappygod** » Mon May 23, 2022 9:45 am

: 13 Why Does The Solar System Rotate 1 Point The Planets Exert Gravitational Forces On Each Other As The Solar Sys 1 (81.6 KiB) Viewed 15 times

13. Why does the Solar System rotate? * (1 Point) The planets exert gravitational forces on each other. As the Solar System formed, its moment of inertia decreased. The Sun exerts gravitational forces that cause the Solar System to rotate. 14. Suppose that you would like to study star A all year round. Its declination is 25 degrees above the celestial equator. At which of the following locations on Earth could you be to observe this star all year round? * (1 Point) at a latitude of 67 degrees N at a latitude of 25 degrees N only at the South Pole at a latitude of 63 degrees N

15. Stars * () (1 Point) contain mostly the same elements, which is why stellar spectra are all very similar. contain very different elements, but produce very different stellar spectra because stellar surface temperatures vary widely. contain mostly the same elements, but produce very different stellar spectra because stellar surface temperatures vary widely. contain very different elements, explaining why stellar spectra vary widely. 16. The spectrum of an atom * (1 Point) consists of one wavelength of light that can be emitted or absorbed by an atom. can only be explained by quantum mechanics, which states that electrons may only orbit atoms in discrete orbits. consists of a continuous set of wavelengths which are emitted or absorbed by the atom. can only be explained by quantum mechanics, which states that electrons may orbit atoms the way that planets orbit the Sun.

17. Out of the following events, which one occurred first in the history of the universe? * (1 Point) the formation of nuclei the formation of the Cosmic Microwave Background. the formation of atoms cosmic inflation 18. The early universe was * (1 Point) contracting expanding, but the expansion was constant. expanding, and that expansion was due to radiation domination. expanding, but the expansion was accelerating due to dark matter.

* 19. The most abundant elements in the universe today (1 Point) are hydrogen and helium, since they were produced only in the cores of stars. are hydrogen and helium, since they do not exist in stars. are hydrogen and helium, since they were most predominantly produced in the early universe. are metals, since these are produced only in the cores of stars. * 20. The equation Af = c means (1 Point) that light travels at different speeds depending on its frequency. that gamma rays, which have very large frequencies, have very small wavelengths. that light travels at different speeds depending on its wavelength. that gamma rays, which have very large frequencies, also have very large wavelengths.