What happens when a star is in hydrostatic equilibrium?
A star is in hydrostatic equilibrium when the outward push of pressure due to core burning is exactly in balance with the inward pull of gravity. When the hydrogen in a star's core has been used up, burning ceases, and gravity and pressure are no longer in balance. This causes the star to undergo significant changes.
What causes the outward pressure that balances the inward pull of gravity in a star quizlet?
What is "hydrostatic equilibrium" in the context of main sequence stars? The outward pressure exerted by hot gas balances the inward pull of gravity.
What stages is a star in energy balance?
The star is in energy balance when its core energy production matches the amount of energy it radiates into space. As explained in the video, this is true only when the star is a main-sequence star with hydrogen core fusion and when it is a helium core-fusion star.
What type of star makes a type II supernova quizlet?
A Type II supernova occurs when a high-mass star's core becomes dominated by iron, halting the nuclear fusion process. The star's core can no longer maintain equilibrium, and the core begins to contract.
What causes the outward gas pressure that balances the inward pull of gravity in a main sequence star?
What holds isotopes of helium together? combines four hydrogen nuclei to form one helium nucleus, which produces energy. What causes the outward gas pressure that balances the inward pull of gravity in a main sequence star? mixes the gases of the star.
What balances with the outward pressure?
the outward pressure of the hot gas inside the Sun balances the inward pull of gravity at every point. this balance is dynamically maintained. an energy balance is also maintained, with the energy produced in the core of the Sun balancing the energy lost from the surface.
What is a stable star called?
White dwarfs are among the most stable of stars. Left on their own, these stars that have exhausted most of their nuclear fuel — while still typically as massive as the Sun — and shrunk to a relatively small size can last for billions or even trillions of years.
What is a Type 1 supernova quizlet?
Type 1a supernovae. a type of supernova that occurs in binary systems (aka two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf.
What is the difference between a nova and a Type 1a supernova?
The major difference between a nova and a supernova is that in a supernova a lot of the object's mass is ejected with the explosion. The amount of this mass is more than the mass of the sun. Where as in a nova, very less mass is ejected as compared to that in a supernova.
How is a star balanced?
You can imagine a star as a series of layers. The inward force of gravity is balanced out by the outward force of pressure to keep the star stable. This stable balance, the outward pressure of hot gases balancing the inward pull of gravity is called the hydrostatic equilibrium.
What is the inward force of gravity balanced by?
neutron degeneracy pressure Inward self-gravity is balanced by neutron degeneracy pressure. Remember that neutron degeneracy pressure is very similar to electron degeneracy pressure. Neutrons are also anti-social!
What is an A class star?
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V (five). These stars have spectra which are defined by strong hydrogen Balmer absorption lines.
Why are they called main sequence stars?
The following year he began studying star clusters; large groupings of stars that are co-located at approximately the same distance. He published the first plots of color versus luminosity for these stars. These plots showed a prominent and continuous sequence of stars, which he named the Main Sequence.
What is Type 2 supernova quizlet?
Type II Supernova. a stellar explosion produced at the endpoint of the evolution of stars whose mass exceeds roughly 10 times the mass of the Sun.
What is the difference between a Type I and II supernova quizlet?
What is the difference between Type Ia and Type II supernovae? Physically, type II supernovae are caused by the collapse of a massive star. Type Ia supernovae are driven by a white dwarf which accretes enough mass to exceed the Chandrasekhar limit and collapses into a neutron star.
What is a nova star?
nova, plural Novas, orNovae, any of a class of exploding stars whose luminosity temporarily increases from several thousand to as much as 100,000 times its normal level.
How is a Type 2 supernova formed?
A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, but no more than 40 to 50 times, the mass of the Sun ( M ☉) to undergo this type of explosion.
What are the balanced forces in a star?
Gravitational forces act to contract the star. Fusion reactions and heat convection act to expand the star. The two forces are balanced and the star remains stable in size and reactions.
What is the inward force that balances the outward force of nuclear fusion?
inward pull of gravity Fusion releases massive amounts of energy as heat and light, so the star ignites. The explosive outward force of fusion is balanced by the inward pull of gravity. The two forces can balance each other for billions of years. Stars in this stable state are called main sequence stars.
What does OH a fine girl kiss me mean?
Every student in introductory astronomy learns the mnemonic “Oh Be a Fine Girl/Guy, Kiss Me”, which is a way to remember the spectral classification of stars. Here's how it works: the color of a star is determined by its temperature, as I outlined previously.
What is the meaning of binary stars?
Binary stars are two stars orbiting a common center of mass. The brighter star is officially classified as the primary star, while the dimmer of the two is the secondary (classified as A and B respectively). In cases where the stars are of equal brightness, the designation given by the discoverer is respected.
What are non main sequence stars?
The common use of "dwarf" to mean main sequence is confusing in another way, because there are dwarf stars which are not main-sequence stars. For example, a white dwarf is the dead core left over after a star has shed its outer layers, and is much smaller than a main-sequence star, roughly the size of Earth.
Which star is a main sequence star?
What is a Main Sequence Star? A main sequence star is any star that has a hot, dense core which fuses hydrogen into helium to produce energy. Most stars in the galaxy are main sequence stars, including Alpha Centauri A, Tau Ceti and the Sun.
What is the difference between type I and Type II supernova?
Type I supernova: star accumulates matter from a nearby neighbor until a runaway nuclear reaction ignites. Type II supernova: star runs out of nuclear fuel and collapses under its own gravity.
What is a Type 1a supernova quizlet?
Type 1a supernovae. a type of supernova that occurs in binary systems (aka two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white dwarf.
What is meant by a binary star?
Definition of binary star : a system of two stars that revolve around each other under their mutual gravitation.
What is a nova and supernova?
A nova is the result of “eruption of a very old dying star”(3); supernova is also the result of a dying star but it is the result of a “violent” explosion of the star (3). Meaning the amount of energy released in a supernova is much greater than that released in a nova; usually this value is about 1044 Joules (4).
How is a Type 1 supernova formed?
A star can go supernova in one of two ways: Type I supernova: star accumulates matter from a nearby neighbor until a runaway nuclear reaction ignites. Type II supernova: star runs out of nuclear fuel and collapses under its own gravity.
How can we distinguish between Type Ia and Type II supernova?
(Review #14, page 325) What is the difference between type Ia and type II supernovae? Observationallly, type Ia supernovae do not have hydrogen line in their spectra and type II supernovae do display these lines. Physically, type II supernovae are caused by the collapse of a massive star.
When a star is stable the forces pushing outwards are?
(b) Figure 2 shows the forces acting on a star when the star is stable. Draw a ring around the correct answer to complete the sentence. When a star is stable, the forces pushing outwards are bigger than smaller than balanced by the forces pulling inwards.