Sunday, January 18, 2009

Percent Accuracy Of Hiv Test After

We are

The other made me such a trick question how many times the earth rotates on itself over a year? Most would say 365, then no. Well that last is true but only half, if we consider the sun. It is true that the earth turns around 366 or so. Now you will wonder why it occurs this curious detail.
To explain this phenomenon we must take into account the definition of solar day, which is the elapsed time between two steps of the sun by the same meridian. But while the earth rotates on itself, is also revolving around the sun, that means that when a land has completed a turn on its axis, the position of the meridian is diverted at an angle, so you must still turn a bit more to complete the day. If we now add these angles "surplus" we see that the sum 360 °, if a loop more. But once made this introduction, I would like to talk a bit more of a concept as day. When the first day I talk to referee a solar day, but there are several types of days you will wonder, yes. Apart from the solar day which is what we use in our daily lives in general, and the cost of 86,400 seconds, which is actually a mean solar day, because this is not regular due to fluctuations in the speed of rotation of the Earth, this is schedule used in civilian life and is denoted as UT1. There is lso apparent solar day, is what is given by the position of the sun in the sky, is related to the mean solar day by calling
equation
time. other hand we can talk or sidereal sidereal day

, but I think the second last prevails, as the time elapsed between two successive steps of a meridian by the First Point of Aries. Its main difference from the solar time is given by the translation movement that made the earth to the sun, which we discussed earlier, when completing a full rotation on itself must move at an angle to maintain the same position on sun, but instead of taking into account the sun we take as reference a distant star this angle becomes almost zero. This means that the solar day is slightly longer than the sidereal day.

Offset between UTC and UT1
But back a moment to mean solar time and us go back to the creation of the International Measurement System. This defined the second initially, depending on the rotation of the earth as part of a day 86,400. Later this definition was changed due to irregularities in the rotation of the Earth, mainly caused by the moon, and the second step to be 9,192,631,770 periods of radiation corresponding to the transition between the two ground state hyperfine levels of the isotope 133 of cesium atom. This new definition was the birth Two new systems of measurement of time on one hand the UTC or coordinated universal time, based on atomic clocks. Due to the high accuracy timing atomic clocks, there is little difference between UTC and solar time. If this difference is less than 0.9 seconds is considered correct, if instead exceeds that level, then adds a second, called leap second to atomic clocks all, to maintain synchrony. But he also appreciates the opportunity to discount a second even never been produced so far. These latter are traditionally added on June 30 or January 1. Although there have been proposals to abolish the leap second replaced by the hour or interlayers, although this proposal were cast down. The other system of measuring the time it came up with the atomic clocks was the International Atomic Time (TAI

) which is analogous to UTC except that it was not added or removed will leap seconds. As there is a difference today from 33 seconds of each other. This is the time used by the majority of equipment needed for handling precision such as GPS. Web Pages Viewed:


Malaciencia .


Sun Dial.
Wikipedia

Microsiervos
About
watches.

Tuesday, January 6, 2009

Laboratory 8:population Genetics And Evolution

Superstring Theory

Whats The Difference Between Condom Types Enz

Bender is our god

In an episode of Futurama, I do not remember the title at this time. Bender just floating through space, but a meteorite crashes into his back and slowly begins to form a new civilization on his back, they were able to talk and communicate. That meant they had atmosphere, but a moment "A robot can generate enough gravity to have an atmosphere around him?



Bender
So all this begs the question Bender gravity is sufficient to create a civilization to develop on its shiny metal ass. To know this we must know what the mass of Bender. To calculate the mass of Bender we will consider having the same volume as a person of 95 kg, that would mean that the volume would be about 0.1 m3. As Bender is made of titanium as it says when you sell your body for a time of shortage of titanium on the land, its weight would be about 450 kg.
Now to continue with our reasoning, let us consider Bender's body is spherical, then its volume to match the actual volume of your radio should be 0.3 m. Now that know what his radio, we can calculate its gravity would be about 1.1 10-7 m/s2. Perhaps too low to have a colony of tiny living things on his back. So I thought that maybe Bender was made with a blade material of the future and could generate close to the lunar gravity, for example, then I started to take bills and discovered that it would weigh about 2.185 million tons to generate a gravitational field similar. That meant that its density must be 21.75 million tonnes per m3, which is totally absurd, except that in the future to build robots used the same stuff that white dwarfs are formed.



Interstellar Space
But despite this slight stumble decided to continue with my reasoning, so I decided to calculate the escape velocity of Bender. To the uninitiated in these matters, is the minimum speed you need to reach an object to escape the gravitational pull of a planet or other body and get to a hypothetical infinite distance with speed 0. But back to the topic at hand, if Bender was made of titanium its escape velocity would be 2.5 10-4 m / s, but if he were made of material of the future blade speed would be approximately 1 m / s. Wow, now if that was beginning to seem reasonable idea Bender floating through space as a civilization developed in his back. So I decided to calculate the rms speed of gas, which is a measure of the velocity of a particle in a gas. If the speed was low enough not to exceed the escape velocity, then Bender would have an atmosphere around him. As the rms speed was directly related to temperature, as we believe that Bender is traveling through interplanetary space where the temperature is 2.7 K, did not seem unreasonable to think that was sufficiently low. Then an atom of hydrogen, the lightest element known, would have an escape velocity 0.8 m / s is not small enough for a titanium Bender had atmosphere but as for a blade Bender had it. Conclusion that unless this Bender made of the same material as white dwarfs or something like it is impossible for dwarves can grow back.

Sunday, December 21, 2008

How To Hack Three Mobile Dongle



Imagine a huge ball of garbage goes from space to New New York, which would you do to deflect it. Okay if you are guinoista maybe your idea of \u200b\u200bHollywood is sending a bomb on one of the failures of the ball to deflect it, but not if you are licensed in physics such as Futurama, dammit. But hey in the end this idea fails, so they decide develop another, even more crazed send another ball of equal mass and consistency to impact against it. It is a much better idea than a bomb, but now think for a moment the mass of garbage that was on the ground.


The film that taught Professor Farnsworth speaks of a garbage crisis in 2000 in New York, at that time its population was only about 8,000,000 people in the metropolitan area. Each person generates about one kilo of waste a day, come think that about half of these wastes are recycled, so do not account for the global computing means that each day New York produced about 4,000 tons of trash daily. If the crisis was so serious as paint waste would send into space a year, a significant amount. That would send into space signicaría approximately 1.5 million tons of trash in the direction of space. So moved by the interest I decided to calculate that energy we would need to accelerate the rocket to escape velocity of the earth. To do this I had to delve into the physics of rockets. Rockets ducted by direct application of Newton's third law: For every force acting on a body, it performs a force equal but opposite to the body that produced it. To do gas combustion occurs within a closed receptacle, such as on both sides of the chamber pressures are equal are to be balanced, while the pressure at the top will produce an absence of pressure thrust on the bottom, so we get an impulse response to the pressure in the combustion chamber .

For a deeper development of the calculations are going to do next, you can visit this page where you will find everything relevant to the physics of rockets. If we now consider the rocket as an isolated system must satisfy the principle of conservation of momentum. If the rocket has an initial mass Mo, the mass after the expulsion of M gases, the exhaust rate of gases Uo the initial time, and volume of gases expelled to the instant t is Dt, and the velocity V, we get that the speed of the rocket can be expressed as:


Therefore we can easily calculate the initial mass that will have the rocket and from it calculate the amount of fuel it carries. If we assume that the speed we want to achieve is the escape velocity of the earth, about 11200 m / s and the initial velocity at which the gases of the rocket is about 2000 m / s. We show that the initial mass of the rocket must be about 9.9 million tonnes. If we now consider that the tenth part ofthe rocket's mass corresponds to the fuel tank, we obtain that 8.4 million tonnes fuel, which also corresponds to Dt, a mass about five times larger than the mass of garbage that we send into space. Now calculate the total energy has necessitated the rocket to reach Earth escape velocity, for it will add the kinetic energy that reaches the rocket, along with the gases expelled from the time to to time t, making the resulting adjustments to obtain energy is determined obtain that need 3.35 x10 ^ 15 joules, about one megaton, the energy released by exploding a nuclear bomb. If instead of using this energy to send into space the garbage had been used to heat large ball away and considering having a heat like the human body you specified: 3470 J / (kg C °), assuming that it is organic matter, the rest has been recycled. The garbage would have reached about 600 degrees. Another noteworthy that chapter, is the Oloroscopio. Totally absurd from the physical point of view. The odors are produced by certain substances to the atmosphere off small molecules that then grasp with our sense of smell. That means that to escape the astrological object in question and be captured by the oloroscopio, the molecules must reach the escape velocity of the planet, that means that the heavier are less likely to reach our planet. You like oloroscopio is located on the surface, means that the molecule must reach through our atmosphere from interplanetary space, something like trying to hit with a dart at any point of a football field. Not only that, to reach our atmosphere would join all the molecules that prevent air swarm know its origin.