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
Power in physics is the rate of energy transferred per unit time. It can be calculated by dividing the amount of energy transferred by the time required for the transfer.
In Physics, power is defined as the rate of transferring energy or the amount of energy per unit time. If you want to calculate the power, you take the amount of energy transferred and divide it by the time it takes for that transfer to occur. For example, if a light bulb transfers 100 joules of energy over 10 seconds, the power would be 100 joules divided by 10 seconds, which equals to 10 watts.
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Answer:
option "c" is correct
Explanation:
Physical science or Physics is the study of matter, energy and their mutual relationship.
Thewave speed will be 210 m/sec. The wave speed is found as the product of the wavelength and frequency of the wave.
The distance between two successive troughs or crests is known as the wavelength. The peak of the wave is the highest point, while the trough is the lowest.
The relationship between the wave's wavelength, time, and speed is given as;
Wavelength = speed of wave / time period
Hence, the wave speed will be 210 m/sec.
To learn more about the wavelength, refer to the link;
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Answer:23hz
Explanation:
Answer: A
Explanation:
I say opposites attract
The answer is A.
Hope this helps :)