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In the last two decades, photovoltaics (PV), also known as solar PV, has evolved from a pure niche market of small scale applications towards becoming a mainstream electricity source. A solar cell is a device that converts light directly into electricity using the photoelectric effect. The first solar cell was constructed by Charles Fritts in the 1880s. In 1931 a German engineer, Dr Bruno Lange, developed a photo cell using silver selenide in place of copper oxide. Although the prototype selenium cells converted less than 1% of incident light into electricity, both Ernst Werner von Siemens and James Clerk Maxwell recognized the importance of this discovery. Following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the crystalline silicon solar cell in 1954. These early solar cells cost 286 USD/watt and reached efficiencies of 4.56%. By 2012 available efficiencies exceed 20% and the maximum efficiency of research photovoltaics is over 40%.
What is a solar cell?
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The answer: a device that converts light directly into electricity

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New chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pure chemicals are used. Care must be taken that the raw materials have not reacted with moisture or other chemicals in the environment (such as alkali or alkaline earth metal oxides and hydroxides, or boron oxide), or that the impurities are quantified (loss on ignition). Evaporation losses during glass melting should be considered during the selection of the raw materials, e.g., sodium selenite may be preferred over easily evaporating SeO2. Also, more readily reacting raw materials may be preferred over relatively inert ones, such as Al(OH)3 over Al2O3. Usually, the melts are carried out in platinum crucibles to reduce contamination from the crucible material. Glass homogeneity is achieved by homogenizing the raw materials mixture (glass batch), by stirring the melt, and by crushing and re-melting the first melt. The obtained glass is usually annealed to prevent breakage during processing.
What material is useful in glassmaking because of its slow evaporation?
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The answer: sodium selenite

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The changes included a new corporate color palette, small modifications to the GE logo, a new customized font (GE Inspira) and a new slogan, "Imagination at work", composed by David Lucas, to replace the slogan "We Bring Good Things to Life" used since 1979. The standard requires many headlines to be lowercased and adds visual "white space" to documents and advertising. The changes were designed by Wolff Olins and are used on GE's marketing, literature and website. In 2014, a second typeface family was introduced: GE Sans and Serif by Bold Monday created under art direction by Wolff Olins.
What was GE's slogan prior to "Imagination at work?"
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The answer: We Bring Good Things to Life

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The ordinary half-wave dipole is probably the most widely used antenna design. This consists of two 14-wavelength elements arranged end-to-end, and lying along essentially the same axis (or collinear), each feeding one side of a two-conductor transmission wire. The physical arrangement of the two elements places them 180 degrees out of phase, which means that at any given instant one of the elements is driving current into the transmission line while the other is pulling it out. The monopole antenna is essentially one half of the half-wave dipole, a single 14-wavelength element with the other side connected to ground or an equivalent ground plane (or counterpoise). Monopoles, which are one-half the size of a dipole, are common for long-wavelength radio signals where a dipole would be impractically large. Another common design is the folded dipole, which is essentially two dipoles placed side-by-side and connected at their ends to make a single one-wavelength antenna.
What is the current usually beng put into it or pulled out of?
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The answer:
transmission line