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krok68 [10]
2 years ago
5

Why are black holes black?

Physics
2 answers:
melomori [17]2 years ago
8 0
Light can't reflect off them I think
Furkat [3]2 years ago
4 0

Black Hole

___________

It is the most mysterious thing in our universe.

✳ John Michell was the first scientist who gave his idea on black hole in 1783

✳ later than Pière simon described black holes in his book the system of the world in 1796.

What are black holes?

=>  It is also a celestial body which have infinite gravitational force and infinite mass and even light can not escape from it.

=> If any object goes near a black hole then time slows down for that object.

How black holes formed?

=> Mostly  black holes formed because of compression of mass and density of stars.

So,  first we know how stars formed and then black holes.

= stars are formed by the cloud of  gas and dust present in our universe which we simply called as Nebula.

= They are mostly composed of hydrogen and helium with some amount of another elements.

= when the density of nebula decreases then they contract because of their  gravitational force and then its temperature rises at very high level and in that temperature hydrogen atom makes helium by fusion reaction and because of the speed of hydrogen atom and also heat the nebula takes a spherical shape which we call star.

Now black hole formation -

= The gravitational force of stats are balanced by their heat.

And hydrogen acts as a fuel for it.

= and when its hydrogen  finishes then with passage of  time that star cools down and then its mass and density  becomes 4 times greater then its original mass and density.

And then that star can't control its gravitational force and then a blast occurs which we call supernova.

And after this blast if any of the piece of that star which have more mass remains then it becomes a star which have mass and density of a critical level and we call this as  Neutron star.

In this type of Neutron star because of its gravitational force then it starts contracting  and after contracting it at a critical level then it becomes a body which have infinite density and mass and because of this infinte density and mass the space time bents inward there and then it doesn't be there and we call this as a black hole.

Its whole mass is focused at center which we call it

✳ central singularity point 

And the boundary of black hole is called

✳ event horizon

And nothing can escape from here even light can't.

And here concept of time doesn't work.

=>  According to theory of relativity if the object is near the black hole then the time slows down for it.

Types of black holes

1. Stellar mass black hole

~> It is the type of black hole formed because of contraction of a star which have mass about 3 times greater than the sun.

2. Super massive black holes

~> It is formed in center of any galaxy and have infinite mass and gravitational force and it has mass about 100000000 times that of sun.

3. Permordial or small black holes

~> They are formed because of the more heat at the center of a star and the mass of that star is less than that of our sun.

Physicist  think that  they formed with the beginning of universe

✳ the nearest black from earth is 

cygnus x1

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Compare the inner core and the outer core?
vfiekz [6]

To compare the inner core and the outer core, we need to outline the parameters based on

  1. Temperature - the outer core has 2000-5000 C, while inner reach 6000 C
  2. Structure and consistency - The outer core consist of iron and nickel, mix with low amount of gold, platinum, and uranium, while inner is the melting pot of all dense material and lot of uranium.
  3. Depth - The outer core has depth to 2900 km, while inner core has 1300 - 1400 km radius.

<h3>Further explanation</h3><h3>Consistency / materials</h3>
  • Both the outer core and the inner core are made generally of iron and nickel.  
<h3 /><h3>Temperature</h3>
  • The outer core achieves a temperature of 2000°c. The inward center has a temperature as high as 5000°c.
  • The inner core achieves a temperature of 6000 °c.
  • Within this temperature, both nickel and iron are dissolved and converted into a fluid.

<h3>Structure</h3>
  • In contrast to the outer core, the internal base is reduced in spite of the boiling temperature achieved the radioactive rot of uranium due to the incredible weight that keeps this layer in a stable stage.
  • The layer that partitions the external center and internal center is known as Bullen brokenness. Bullen brokenness is likewise the most sizzling locale of wherein the temperature reaches up to 6000°c its as hot as the outside of the sun.

<h3>Depth </h3>
  • Outside the outer and inner core, there is mantle that has the depth to around 2,900 kilometers from the Earth's surface.
  • The outer has depth more than 2900 kilometers from Earth surface.
  • The iner core is the deepest among all of them and has radius for 1300 kilometers.
  • Check the structure of earth here brainly.com/question/2162876

<h3>Structure of Earth</h3>

The Earth is separated into four layers. The external layer is the hull, beneath the covering is the mantle, and pursued by the external center, at that point, the most profound and the most smoking layer is known as the internal center.

<h3>Learn more</h3>

Here are the four layers of the Earth

  1. Hull
  2. Mantle
  3. External center
  4. Internal center

<h3>1. Hull or crust </h3>

The hull is the peripheral and the thinnest layer which goes about as the skin of the Earth that stretches out from the surface to around 32 kilometers beneath. This is the layer where we live, and volcanoes, quake, and mountain reaches are framed.

  • The marine shell is denser and more slender contrasted with mainland hull.
  • Mainland hull is thicker and is less thick contrasted with the maritime shell.

<h3>2. Mantle </h3>

Underneath the outside is the layer known as the mantle, which stretches out to around 2,900 kilometers from the Earth's surface. The coat is the thickest layer of the Earth and is progressively thick contrasted with the outside. It is the path more sizzling than the covering and equipped for liquefying it. The upper mantle is plastic, its made up of magma that as a result of an excessive amount of warmth it streams which causes changes on the outside of the Earth.

<h3>3. Outer Core </h3>

The external center is 2900 kilometers underneath the outside of the Earth. It is for the most part comprised of iron and nickel; however, in the fluid stage and its temperature ranges to about 2000°C. Regardless of whether the external center has a high weight, yet because of its a lot higher temperature, nickel and iron are liquefied. The external center is streaming outside the internal center, which produces an attractive field that shields the Earth from the hazardous, radioactive material originating from the warmth of the sun.

<h3>4. Internal Core </h3>

The internal center is the most profound layer comprised of heavy iron and nickel and has a sweep of around 1,300 kilometers. Its temperature scopes to about 5000°C. The internal has the most elevated thickness contrasted with the other. The warmth in the inside of the Earth is brought about by the radioactive rot of uranium in the internal center, which discharges considerable measure of heat.

Perhaps you are interested within the topic of

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<h3>Core Curriculum category</h3>

Subject : Geography

Class : 8

Subchapter : Earth and its structure.

4 0
3 years ago
Read 2 more answers
Which temperature is the hottest? 98 F or 39 C or 303K?<br> F= 1.8C + 32<br> C= (F-32)/1.8
sergejj [24]

Answer:

The hottest temperature is  T_2 = 39^o C

Explanation:

From the question we are given

    T_1 =  98 F

  T_2 =  39^oC

  T_3 =  303 \  K

Generally converting T_3 to  Fahrenheit

    T_3' =  (T_3 -273 ) * \frac{9}{5}  + 32

=> T_3' =  (303 -273 ) * \frac{9}{5}  + 32

=> T_3' = 86 F

Converting  T_2 to  Fahrenheit

      T_2' =  T_2 * \frac{9}{5}  + 32

=> T_2' =  39 * \frac{9}{5}  + 32

=> T_2' =102.2 F  

Now comparing  the temperature  in Fahrenheit we see that T_2  is the hottest

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What happens when infrared hits a shiny surface
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Will reflect ........
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The rate at which a candle burns in millimeters per minute is:
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since both components, length and time, are measurable 
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<span>∴ rate is also measurable and ∴ quantitative.

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3 years ago
Which organisms play roles similar to organisms in water ecosystem
lina2011 [118]
Is there a multiple choice?
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