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Weber (unit) From Wikipedia, the free encyclopedia Jump to: navigation, search In physics, the weber (symbol: Wb;  /ˈveɪbər/, /ˈwɛbər/, or /ˈwiːbər/) is the SI unit of magnetic flux. A flux density of one Wb/m2 (one weber per square meter) is one tesla. The weber is named for the German physicist Wilhelm Eduard Weber (1804–1891). [edit] Definition

The weber may be defined in terms of Faraday's law, which relates a changing magnetic flux through a loop to the electric field around the loop. A change in flux of one weber per second will induce an electromotive force of one volt (produce an electric potential difference of one volt across two open-circuited terminals). Officially,

Weber (unit of magnetic flux) — The weber is the magnetic flux which, linking a circuit of one turn, would produce in it an electromotive force of 1 volt if it were reduced to zero at a uniform rate in 1 second.[1]

A particle carrying a charge of 1 coulomb and passing through a magnetic field of 1 tesla at a speed of 1 meter per second perpendicular to said field experiences a force of 1 newton, according to the Lorentz force law. As an SI derived unit, the tesla can also be expressed as (in SI base units).[3] Units used: A = ampere C = coulomb kg = kilogram m = meter N = newton s = second T = tesla V = volt Wb = weber [edit] Electric vs Magnetic Field

The difference between magnetic field strength (in tesla) vs electric field strength can be confusing.[citation needed] The difference is that a force of magnetic field on a charged particle is generally due to the charged particle's movement[4] while the force imparted by an electric field on a charged particle is not due to the charged particle's movement. This can be seen by looking at the units for each. Electric field is N/C, while magnetic field (in tesla) can be written as N/(C*m/s). The difference between the two is m/s, or velocity. This can further be seen by noting that whether a field is magnetic or electric is dependent on one's relativistic reference frame (that is: one's velocity relative to the field).[5][6] In ferromagnets the movement creating the magnetic field is the electron spin[7] (and to a lesser extent electron orbital angular momentum). In current carrying wire (electromagnets) the movement is due to electrons moving through the wire (whether the wire's straight or circular).

Metre From Wikipedia, the free encyclopedia   (Redirected from Meter) Jump to: navigation, search This article is about the unit of length. For other uses of "metre" or "meter", see meter (disambiguation). 1 metre = SI units 100 cm 1000 mm US customary / Imperial units 3.2808 ft 39.370 in The metre (meter in the US), symbol m, is the base unit of length in the International System of Units (SI). Originally intended to be one ten-millionth of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it has been defined as "the length of the path travelled by light in vacuum during a time interval of 1 ⁄ 299,792,458 of a second.[1]

Newton (unit) From Wikipedia, the free encyclopedia Jump to: navigation, search Not to be confused with Newton scale, a rarely used non-SI temperature scale. Newton Unit system: SI derived unit Unit of... Force Symbol: N Named after: Isaac Newton In SI base units: 1 N = 1 kg·m/s2 The newton (symbol: N) is the SI derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion.

Second From Wikipedia, the free encyclopedia Jump to: navigation, search This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second The second (SI unit symbol: s) is the International System of Units (SI) base unit of time[1] and also a unit of time in other systems (abbreviated s or sec[2]). Between 1000 (when al-Biruni used seconds) and 1960 the second was defined as 1/86,400 of a mean solar day (that definition still applies in some astronomical and legal contexts).[3][4] Between 1960 and 1967, it was defined in terms of the period of the Earth's orbit around the Sun,[5] but it is now defined more precisely in atomic terms. Seconds may be measured using mechanical, electric or atomic clocks.

Kilogram

The kilogram or kilogramme (SI symbol: kg), also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal to the mass of one liter of water. The avoirdupois (or international) pound, used in both the Imperial system and U.S. customary units, is defined as exactly 0.45359237 kg, making one kilogram approximately equal to 2.2046 avoirdupois pounds.

Ampere

The ampere (SI unit symbol: A), often shortened to amp, is the SI unit of electric current[1] (quantity symbol: I,i)[2] and is one of the seven[3] SI base units. It is named after André-Marie Ampère (1775–1836), French mathematician and physicist, considered the father of electrodynamics. Note that SI supports only the use of symbols and deprecates the use of any abbreviations for units.[4]

Volt From Wikipedia, the free encyclopedia Jump to: navigation, search For other uses, see Volt (disambiguation). Josephson junction array chip developed by NIST as a standard volt The volt (symbol: V) is the SI derived unit for electric potential, electric potential difference, and electromotive force.[1] The volt is named in honor of the Italian physicist Alessandro Volta (1745–1827), who invented the voltaic pile, possibly the first chemical battery.

A single volt is defined as the difference in electric potential across a wire when an electric current of one ampere dissipates one watt of power.[

The U49325 Sun Runner Stirling Engine is a solar-powered Stirling Engine which offers a dramatic demonstration of energy conversion.   This motor and its parabolic mirror can be attached to any conventional camera tripod. When properly aimed at the sun, the polished aluminum parabolic mirror focuses incoming solar energy on the heat cap of the engine, which is converted to rotary motion. Unit comes complete with motor, parabolic mirror, and wrenches. Standard camera tripod is not supplied. This engine is completely assembled and ready to run. Each unit is test run at the factory prior to shipping. Motor runs at 2,000 RPM and up. This engine can also run as a horizontal engine with an alcohol burner. Demonstrate this exciting method of harnessing the sun’s clean and renewable energy to your students.  Weight: 6.00 lbs Dimensions: Engine: 8.25 x 3 inches (L x W) Flywheel: 3.25 inchesParabolic Mirror: 18 inch diameterPlease note that this item is designed to demonstrate the operating principles of a Stirling engine for educational use and is not designed for power production.  It can potentially be coupled with a generator for producing very small amounts of electricity but is incapable of powering anything beyond a small light bulb or LED.

The unit is light weight (2.5 lb), portable, low cost ($10-$20) and can be used to recharge single cell batteries at from 1-3.5 amps. It can be made from a cordless electric drill in a primitive environment. The simplest way of how to make a hand crank DC generator using a standard 12, 14.4 or 18 Volt Cordless drill

With no modification hook an alligator clip jumper to the two charging terminals (on the bottom that the battery plugs into). See picture below. Note that when a 14.4 Volt drill is laid down pointing to the left then the upper terminal is most likely to be the plus and the lower terminal the minus for these units.

Coulomb

The coulomb (symbol: C) is the SI derived unit of electric charge. It is defined as the charge transported by a steady current of one ampere in one second: One coulomb is also the amount of excess charge on the positive side of a capacitance of one farad charged to a potential difference of one volt:

Light-emitting diode

A light-emitting diode (LED) is a semiconductor light source.[3] LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Introduced as a practical electronic component in 1962,[4] early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. When a light-emitting diode is forward-biased (switched on), electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence and the color of the light (corresponding to the energy of the photon) is determined by the energy gap of the semiconductor. LEDs are often small in area (less than 1 mm2), and integrated optical components may be used to shape its radiation pattern.[5] LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, live video, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.

Processor   CPU GPU Operating System Memory ROM ARM Cortex A9, 1GHz CPU Mali™-400MP Graphics Processing Unit Android 2.3 Gingerbread. Will be updated later to Android 4.0 ICS 512MB (optional 256MB) Built-in 4GB NAND Flash Interfaces   Networking USB Power SD HDMI Built in WiFi module 802.11b/g/n 10/100Mbps with internal antenna USB 2.0 HOST port Mini USB port for power supply (1A required) Micro SD card slot, support up to 32GB HDMI 1.3 OUTPUT (Video and Audio)

ASUS lifted the veil over its long-awaited redesigned 9.2mm thin PadFone at the MWC. Sporting a 4.3-inch Super AMOLED qHD display, Snapdragon S4 with the new Adreno 225 GPU, and 8MP camera with LED flash and f/2.2 aperture, as well as 16-64GB of internal storage plus microSD slot, it has what we would expect from a modern high-end. Connectivity is taken care of 42Mbps HSPA+ radio, Wi-Fi, Bluetooth 4.0, HDMI and A-GPS, while a 1,520mAh battery unit is included as a juicer. The Padfone can get inserted into an optional tablet frame, whose 10.1 inch screen then gets powered by the phone itself, and can extend your battery life significantly. There is another dock, which allows you to add a detachable keyboard accessory, like on the Transformer Pad series. This one also comes with a stylus that except for doodling can be used to receive your phone calls as well, considering that the phone is inserted in the mothership.

USS Lincoln VS canada This is the translation of the ACTUAL radio conversation of a U.S. naval ship with the Canadian authorities off the coast of Newfoundland. The Chief of Naval Operations on October 10th 1995 released the radio conversation. Canadians: Please divert your course 15 degrees to the South to avoid a collision. Americans: Recommend you divert your course 15 degrees to the North. Canadians: Negative. You will have to divert your course 15 degrees to the South to avoid a collision. Americans: This is the Captain of a US Navy ship. I say again, divert YOUR course. Canadians: No. I say again, you divert YOUR course. Americans: THIS IS THE AIRCRAFT CARRIER USS LINCOLN. THE SECOND LARGEST SHIP IN THE UNITED STATES ATLANTIC FLEET. THREE DESTROYERS, THREE CRUISERS AND NUMEROUS SUPPORT VESSELS ACCOMPANY US. I DEMAND THAT YOU CHANGE YOUR COURSE 15 DEGREES NORTH, I SAY AGAIN, THAT'S ONE FIVE DEGREES NORTH, OR COUNTERMEASURES WILL BE UNDERTAKEN TO ENSURE THE SAFETY OF THIS SHIP. Canadians: We are a lighthouse. Your call.