astronomy ch. 15
A star leaves the horizontal branch in the HR diagram when
it runs out of helium at its core.
When a star first moves off the main sequence,
its surface temperature drops and its brightness first stays about the same and then increases.
When the temperature of a gas increases, its molecules
move faster
Which of the following particles would be attracted to a neutron through the strong force?
proton
Our Sun is a type G2V star on the main sequence. As it ages and uses up its fuel we expect it to
remain a G2V star until it leaves the main sequence.
When a red giant star begins to burn helium, it
returns part way to the main sequence in an HR diagram.
The period of a proto-star's evolution when its size and brightness decrease just before the ignition of nuclear reactions in its core is called
the Tau Tauri phase.
The mass of a carbon atom is 12.00amu while the mass of a helium-4 atom is 4.003amu. If a gamma ray photon splits a carbon atom into three Helium atoms, how much energy is converted into mass?
0.009amu
The diameter of a white dwarf star might be
10,000 miles
Which of the following star-like objects would most likely be considered to be a brown dwarf?
Gliese 229B, luminosity and temperature both below type M9V.
For a star to give rise to a Nova, the star must be
a member of a multiple star system.
An atom of ordinary hydrogen consists of a proton and
an electron
Which of the following particles would be electrically attracted by a positron?
an electron
The onset of Helium burning at the core of a star normally begins with
an explosion in the helium core.
Because of the electrical repulsion between atomic nuclei, nuclear fusion happens only
at high temperatures.
When nuclear fusion reactions stop in a star similar to our own Sun, the star
becomes a white dwarf.
The light from a new-born white dwarf star will most likely be
blue
A star leaves the main sequence when
it runs out of Hydrogen at its core.
The mass of Betelgeuse is about 20 times the mass of our own Sun. Our Sun is expected to have a total life span of about 10 billion years. The life span of Betelgeuse is expected to be
much shorter.
Which of the following particles has almost the same mass as a proton?
neutron
Electron degenerate matter is matter in which
the electrons are touching each other so that they cannot be compressed.
