Generate Lighting At Home

During rainy reason,there are peoples sitting outside and watching the sky for thunderbolt. It is amazing,but in other hand dangerous too. Lightningis a natural phenomena of electric discharge between clouds and Earth. The patterns generated during lightning is very beautiful than Monalisa. It is not possible to frame these patterns. If you would like to enjoy the beauty always, there is a device for generating Lightning at your home as you like.
How this instrument works?, we know that when there is an enough potential difference to brake the air resistance charge will flow from one point to another. How could we reach this much potential? In 1929 an American physicist Robert J Van de Graff invented a electrostatic generator which uses a moving belt to accumulate very high voltages on a hollow metal globe on the top of the stand. The device is named as Van De Graff Generator.

Working principle
"if a hollow conductor made contact with a charged conductor,the charges on the conductor will be transferred to the hollow conductor irrespective of its own potential "
xperimental arrangement
A Van De Graff Generator consists of a large spherical conducting shell of radius few meters supported at several meters above the ground on an insulating column. A long narrow insulating belt is wounded around two pulleys one at ground level and one at the center of sphere or shell at the top. The belt continusly carries positive charges sprayed on it by a brush at ground level to the top. There it transfers throug another conducting brush connected to the large shell. The charge will transfer to the outer shell irrespective of the charge of inner shell. The positive charge transfered to the shell spread uniformlely on the outer surface. A modern generator could generate 5 MV potential difference.
Applications of Van De Graff Generator
1. Sterilize food
2. Accelerating photons
3. Driving X-ray tubes

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What About The Energy?

In high school's energy is defined as the ability to exert push or pull against the basic forces of nature,along a path of certain length. The basic forces are,
1. Gravitational force: this force acts between all mass in the universe and it has infinite range.
2. Electromagnetic force: Electricity magnetism and light are all produced by this force and it also has infinite range. The force acts between electricially charged particles.
3. The strong force: this force binds neutrons and protons together in the cores of atoms and it is a short range force.
4. The weak force: this causes betadecay. Like strong force,the weak force also short range.
According to the theory of conservation of energy,energy can neither be created nor be destroyed. But after high school,a doubt arised in my head about the conservation of energy. Now a days,there are plenty of research organizations who are trying to makeup the energy efficiency of electronic and nonelectronic devices. According to senseses 80 percent of the energy generated are waste after applying to a machine or device. How this energy loss occurs?
What about the energy flowing through a bulb? Have you ever think as me? We know that the electric energy is converted to light energy and heat energy in a bulb. But we dont know where there light and heat energy hides? Do it converted in to any other form?
At the end of 2011, I found its answer in a science magazine. They explained that the energy lossed from not only electronic but also non-electronic equipments are used to change the total Entropy of the universe. I don't know how much it is true?. Do this energy have been accumulating somewhere in the universe? An extreme source of energy?

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Liquid Crystal Design

Liquid crystals , ubiquitous in cell-phone screens and computer monitors, were known to science long before engineers realized their utility in displays and other technologies. Now, an international team of researchers has discovered how to use liquid crystals as scaffolding to build novel materials with undiscovered properties.
Reporting their findings in the journal Nature on May 3, the researchers describe a sophisticated computational model for determining how liquid crystals behave within the confines of nanometer-scale droplets containing molecules that lower the surface tensions of liquids, called surfactants.
The researchers, led by University of Wisconsin-Madison engineer Juan de Pablo , show that as the droplets cool, the liquid crystals confine the surfactant molecules, organizing them into discrete structures.
As the researchers adjusted the model's parameters, such as droplet size or surfactant concentration, the simulation revealed that it is possible to use the technique to guide self-assembled structures with awide range of properties and applications.
For example, the researchers suggest the technique could be used to construct materials from DNA building blocks, allowing unique detectors for biological materials and toxins.
"The researchers have taken a new and exciting approach to the study of liquid crystals, which will have impact in several scientific and technical arenas," adds Mary Galvin, National Science Foundation (NSF) program director for Materials Research Science and Engineering Centers.
NSF supported the research through the University of Wisconsin-Madison's Center on Nanostructured Interfaces , an NSF Center of Excellence for Materials Research and Innovation.
For more information, read the full University of Wisconsin-Madison press release

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