Theory CONDUCTORS‚ INSULATORS AND CONDUCTIVITY Conduction of electricity in electric circuits takes place due to the presence of excess electrons in materials called conductors. Electrons move in the direction in which the potential has been applied. The ability of a conductor to conduct electricity is directly proportional to the material’s area of cross section and inversely proportional to its length. Where‚ G is conductance σ is conductivity A is area of cross section
Premium Semiconductor
which released the most amount of energy‚ is potassium nitrate. Because the amount of energy light produces is depended on the frequency (colour) of the light‚ and potassium nitrate produced a light purple colour. According to the visible spectrum‚ a photon of purple had more energy than any other colour produced in this lab‚ because purple light has shorter wavelength (approximately 380-450 nm) and shorter wavelength means higher frequency which also means higher energy. Therefore we can conclude that
Premium
SUMMER INTERNSHIP REPORT FINITE ELEMENT TRANSIENT THERMAL ANALYSIS OF LASER WELDING PROCESS ABSTRACT In this project‚ Laser welding process has successfully been used for joining of two stainless steel plates. The sizes of the metal plates are 50mmX40mmX2mm each. The distribution of the temperature field in laser welding using stainless steel sheets were simulated by ANSYS. The thermal properties which have been used for thermal simulation are assumed to be varying with temperature
Premium Welding
Why do we have rods and cones? Light falling on photoreceptors is transformed by retinal circuitry into a pattern of action potentials that ganglion cell axons convey to the visual centres in the brain. Two systems of photoreceptors exist – rods and cones – allowing the visual system to meet the conflicting demands of sensitivity and acuity‚ respectively. Rods and cones are distinguished by shape‚ type of photopigment they contain‚ distribution across the retina‚ and pattern of synaptic connections
Premium Retina Eye Photoreceptor cell
Electrical technology – assignment 4 Properties of electrical materials and Effective use of technology P.5. Describe the properties and a typical application of a solid and a liquid or gas electrical conductor. A conductor is a material that allows free movement of electrons and therefore allows easy flow of electricity. Most conductors are metals. A common metal used as a conductor in electrical technology is aluminium. It is used quite a lot as it cheap‚ lightweight and in abundance compared
Premium Magnetism Magnetic field Magnet
nuclear‚ electromagnetic and gravity were combined as a single "super force" (Wald). Elementary particles known as quarks begin to bond in trios‚ forming photons‚ positrons and neutrinos and were created along with their antiparticles. There are minuscule amounts of protons and neutrons at this stage; approximately 1 for every one billion photons‚ neutrinos or electrons (Maffei). The density of the Universe in its first moment of life is thought to have been 1094g/cm3 with the majority of this being
Premium Big Bang Physical cosmology Redshift
vira@ymail.com Abstract Most of the smoke alarms available in the market use one or another kind of smoke sensor which increases the cost and also require complicated interfacing circuitry around it. But this smoke alarm circuit uses readily available photon-coupled interrupter module as smoke detector. The functioning of this smoke alarm is to continuously detect smoke and automatically activate the alarm in case of dense smoke. Loud sound is heard continuously indicating the presence of smoke till smoke
Premium Integrated circuit Smoke Alarm
Basic Electronics Semiconductor —I • Materials that permit flow of electrons are called conductors (e.g.‚ gold‚ silver‚ copper‚ etc.). • Materials that block flow of electrons are called insulators (e.g.‚ rubber‚ glass‚ Teflon‚ mica‚ etc.). • Materials whose conductivity falls between those of conductors and insulators are called semiconductors. • Semiconductors are “part-time” conductors whose conductivity can be controlled. germanium Semiconductors silicon
Premium Semiconductor
SUPER CONDUCTORS Superconductivity is an electrical resistance[->0] of exactly zero which occurs in certain materials[->1]below a characteristic temperature[->2]. It was discovered by Heike Kamerlingh Onnes[->3] in 1911. Likeferromagnetism[->4] and atomic spectral lines[->5]‚ superconductivity is a quantum mechanical[->6]phenomenon. It is also characterized by a phenomenon called the Meissner effect[->7]‚ the ejection of any sufficiently weak magnetic field from the interior of the superconductor
Premium Superconductivity
many theories as to why prophetic dreams occur. One theory details the possible experience of a future event through time distortion caused by the dream state. “Dreams involve the generation and perception of bio-photons. The Lorentz temporal dilatation during dream periods for bio-photons with THz frequencies is 3 to 4 days which is an average value between dream experiences and later events” (Dotta & Persinger‚ 2009). In simpler terms‚ certain parts of the brain work at a higher rate during the
Premium Abraham Lincoln President of the United States Ulysses S. Grant