Black Holes
Black holes are objects so dense that not even light can escape their gravity, and since nothing can travel faster than light, nothing can escape from inside a black hole. Loosely speaking, a black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull. Since our best theory of gravity at the moment is Einstein's general theory of relativity, we have to delve into some results of this theory to understand black holes in detail, by thinking about gravity under fairly simple circumstances.
Suppose that you are standing on the surface of a planet. You throw a rock straight up into the air. Assuming you don't throw it too hard, it will rise for a while, but eventually the acceleration due to the planet's gravity will make it start to fall down again. If you threw the rock hard enough, though, you could make it escape the planet's gravity entirely. It would keep on rising forever. The speed with which you need to throw the rock in order that it just barely escapes the planet's gravity is called the "escape velocity." As you would expect, the escape velocity depends on the mass of the planet: if the planet is extremely massive, then its gravity is very strong, and the escape velocity is high. A lighter planet would have a smaller escape velocity. The escape velocity also depends on how far you are from the planet's center: the closer you are, the higher the escape velocity . The Earth's escape velocity is 11.2 kilometers per second (about 25,000 M.P.H.), while the Moon's is only 2.4 kilometers per second (about 5300 M.P.H.). We cannot see it, but radiation is emitted by any matter that gets swallowed by black hole in the form of X-rays. Matter usually orbits a black hole before being swallowed. The matter spins very fast and with other matter forms an accretion disk of rapidly spinning matter. This accretion disk heats up through friction to such high temperatures that it emits X-rays. And also there is some X-ray sources which have all the properties described above. Unfortunately it is impossible to distinguish between a black hole and a neutron star unless we can prove that the mass of the unseen component is too great for a neutron star. Strong evidence was found by Royal Greenwich Observatory astronomers that one of these sources called Cyg X-1 (whic...
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...detect this radiation was Joseph Weber. He eventually came up with the first bar gravity-wave detector. This was a long aluminum cylinder, 2m by ½m, that should be compressed with an incoming gravity wave. To detect this compression he wired piezoelectric crystals, which respond to pressure by generating an electric current, to the outside surface of the bar. Although it didn't work, other bar detectors were built that used a device called a stroboscopic sensor to filter out random vibrations. This was an ingenious device, but it too proved to be a non-contributor in the advancement of learning more of the galaxy. Just as X-ray astronomy went from simple detectors in the noses of rockets to full fledged X-ray telescopes housed in orbiting satellites, and radio astronomy went from crude dishes to continent spanning arrays, gravity wave detectors may show a completely new spectrum. And, just as X-rays brought a completely new universe into focus, one can hardly imagine what a gravitational view of the universe will reveal. At the very least, we will have definitive proof or denial of black holes, but we may find that black holes are some of the more subtle features of the universe.
Starting with black holes, Khalili describes the creation of one. I found that a black hole is what remains when a massive star dies. Because stars are so massive and made out of gas, there is an intense gravitational field that is always trying to collapse the star. As the star dies, the nuclear fusion reactions stop because the fuel for these reactions gets burned up. At the same time, the star's gravity pulls material inward and compresses the core. As the core compresses, it heats up and eventually creates a supernova explosion in which the material and radiation blasts out into space. What remains is the highly compressed and extremely massive core. The core's gravity is so strong that even light cannot escape. This object is now a black hole and literally cannot be seen because of the absence of light. Because the core's gravity is so strong, the core sinks through the fabric of space-time, creating a hole in space-time. The core becomes the central part of the black hole called the singularity. The opening of the hole is called the event horizon. Khalili describes that there are two different kinds of black holes:
In the first part of the book, Siddhartha is consumed by his thirst for knowledge. He joined the samanas and listened to the teachings of the Buddha in attempt to discern the true way to Nirvana. Though he perfected the arts of meditation and self-denial, he realized that no teachings could show him the way to inner peace. While with the ascetics only a third of his quest was accomplished. Siddhartha said, "You have learned nothing through teachings, and so I think, O Illustrious One, that nobody finds salvation through teachings" (27). His experiences with the samanas and Gotama were essential to his inner journey because they teach him that he cannot be taught, however this knowledge alone would not deliver him to enlightenment. Siddhartha had taken the first step in his quest but without the discovery of the body and spirit, his knowledge was useless in attaining Nirvana.
One example of an archetype in The Pearl is the Hero, who is played by Kino, the main character. On page 5 of The Pearl John Steinbeck the author writes, “It sensed danger when Kino was almost in reach of it.. It stopped and it tail rose up over its back in little jerks and the curved thorn on the tails end glistened… Kino's hand leaped hand reached out to catch it, but it fell past his fingers and onto the baby's shoulder.” In this quote Kino is about to try and stop his baby from getting stung by a scorpion by trying to catch it so it doesn't sting and hurt his
A black hole is a dead star in outer space. It is where planets and stars disappear at. The gravity of a black hole is way too strong ( Aguilar 39). The black hole is a weird object in outer space and a black hole is formed when two giant stars or more collapse together and basically vacuum anything that comes near it ( Aguilar 39). It might be gases around the black hole. People call it a black hole because light can’t escape from it (Cool Cosmos). So the hole appears black and the volume of the black hole is zero (Cool Cosmos).
A Black Hole is defined as an object in space that is so compact, that has a gravitational pull so powerful, not even light can escape its pull. In most cases Black Holes are formed when a massive star (much larger than our own) undergoes a supernova explosion. When this happens, the star may collapse on its own gravitational pull, thus resulting in a an object with infinitely large density and zero volume. As a result, the escape velocity (the speed required to escape the gravitational pull) becomes even greater than the speed of light, and because nothing can travel faster than the speed of light, nothing can escape a black hole.
Black holes are points in space where there are extreme gravitational pulls that prevent anything, including light, from escaping. The reason for such a strong gravitational pull is due to vast amounts of matter being contained in a small amount of space. Stellar black holes form from stars with a mass greater than 20 solar masses and can be a result of gravitational collapse. Gravitational collapse is a result of the star’s internal pressure not being able to resist the stars own gravity. When the star is exhausted of its nuclear fuel such that it cannot maintain a high enough temperature it will begin to collapse under its own weight (Seidel 2011). As the star collapses it causes a supernova which blasts the outer layers of the star into space while the core completely collapses under its own weight. If the remnant core left behind exceeds 3 solar masses there are no known forces that can prevent the core from completely collapsing into a black hole (p. 568 Bennett et al. 2013)
A Black hole is a theorized celestial body whose surface gravity is so strong that
A reason that bottled water has been valued over tap water would be that it is more portable. It is more convenient to just go and pick up a bottle of water than have to fill something up and take it with you. If you are in a time crunch you would
Meeting Gotama, the Buddha, is a turning point in Siddhartha’s path towards wisdom. Gotama claims his way of living is the true way of salvation, but Siddhartha thinks that there is a gap in his lessons. Siddhartha says to the Buddha, “You have learned nothing through teachings, and so I think, O Illustrious One, that nobody finds salvation through teaching. To nobody, O Illustrious One, can you communicate in words and teachings what happened to you in the hour of enlightenment” (p. 33). Even though Siddhartha considers the Buddha as an enlightened, wise person, he believes that his teachings are unreliable. Gotama has found enlightenment through his own experience. Since Gotama’s followers cannot go through what he has experienced, he cannot transmit his wisdom to his followers. Indeed, knowledge can be gained from external sources, such as teachers and books; however, wisdom is spiritual and can be only found through experience. Siddhartha decides to not rely on the Buddha's teachings. Different from Siddhartha, Govinda admires the Buddha’s doctrines and becomes one of his followers. Eventually, Siddhartha finds enlightenment by listening to a river. When
...d in acts to try and please God or whom ever they wish to gain forgiveness from. Most people naturally tie depression to death; people in this stage will experience sadness, regret, and fear of what is to come. The final stage is acceptance, this stage is very straightforward, it is in this stage that the individual realizes their fate and are okay with it and what they have done. (Elisabeth Kübler-Ross -Five Stages of Grief, Business Balls). Dimmesdale is a very, very troubled man to say the least. Throughout The Scarlet Letter Dimmesdale is shown going through the five stages of grief, he lets his sin rule and control his life and lets it ultimately lead to his demise.
My research question: Is the convenience of bottled water worth all the sacrifices in terms of money, resources, health and damage to the ecosystem?
The data provided by IBWA (International Bottled Water Association) reveal that bottled water has become extremely popular in the US market. More that $11 billion dollars has been spent for the consumption of bottled water and its consumption increase three times in the last 10 years. The market of bottled water in the United States is the second largest apart from the soft drink. In 2006, the U.S consumption of bottled water was more than 32 billion liters compared to 20 billion liters consumed in 2001. Yearly, an individual in Houston consumes average of 90.5 liters of water more than global average of 24.2 liters. Such growth in the consumption of bottled water is presumable consumers’ perception about safety, purity and convenience of bottled water. Typically, increasing public awareness of bottled water makes 50% of Houston population to drink bottled water and approximately one-third of Houston population drink bottled water regularly. Since 1976, there has been an increase in the market of bottled water in Houston and the United States as a whole. (See Fig 1).
...e times the mass of the sun. In this case gravity is overwhelmingly strong and is able to crush the neutron star towards zero mass. The result is a black hole with a gravitational field strong enough to not even let light escape (Brusca, 2004).
households have at least one individual who was victimized in some way during the past year. Personal theft is very common. About 99% of Americans will be the victim of personal theft at some time in their lives, and 87% will be a theft victim three or more times. Men are twice as likely as women to be victims of robbery and assault. The violent victimization rate for females has been fairly stable, but there has been a 20% increase for males in the last 15 years. Victim risk diminishes rapidly after age 25, It usually draws more attention when elderly people are victimized, but they are usually safer than their children or grandchildren. Unmarried or never married people are more likely to be victims than the married or widowed (Roberts, 2017).