Author Question: Current evidence suggests that the Universe is a. flat, infinite, and neither expanding nor ... (Read 222 times)

iveyjurea · **on:** Jul 27, 2018

Current evidence suggests that the Universe is

a. flat, infinite, and neither expanding nor contracting.
b. closed, finite, and slowing its expansion.
c. open, infinite, and slowing in its expansion.
d. static with no expansion.
e. flat, infinite, and accelerating in its expansion.

Question 2

If the Sun and stars are supported by gas pressure, what supports a white dwarf?

What will be an ideal response?

Benayers · **Reply #1 on:** Jul 27, 2018

Answer to Question 1

e

Answer to Question 2

A normal star is supported by energy flowing outward from its core, but a white dwarf can't generate energy by nuclear fusion. It has exhausted its hydrogen and helium fuels and converted them into carbon and oxygen. When a star collapses into a white dwarf, it converts gravitational energy into thermal energy. Its interior becomes very hot, but it can't get hot enough to fuse its carbon-oxygen interior. Instead the star contracts until it becomes degenerate. The white dwarf is supported against its own gravity by the pressure of its degenerate electrons.