What Is Electrical Energy?

On a diesel-electric locomotive, a diesel engine provides power to an electric traction motor that turns the unit's wheels.
On a diesel-electric locomotive, a diesel engine provides power to an electric traction motor that turns the unit’s wheels.

Electrical energy results from the movement of an electrical charge, and is commonly referred to as simply “electricity.” Ultimately, it has its origin in the electromagnetic force: one of the four fundamental forces of nature and the one that is responsible for the behavior of electrically charged objects. Electrical energy is the result of the interaction of subatomic particles with this force. Electricity manifests itself in natural phenomena such as lightning and is essential to life at a fundamental level. The ability of humans to generate, transmit and store electricity is crucial to modern industry, technology and, in most countries, domestic life.

The Origin of Electrical Energy

There are two types of electrical charge, called positive and negative. If two electrically charged objects are brought close to one another, they will experience a force. If the charges are the same — both positive or both negative — the force will act to push the objects away from one another. If they have different charges, they will attract one another. This repulsion or attraction is known as the electromagnetic force, and it can be harnessed to create a flow of electrical energy.

Atoms consist of a nucleus containing positively charged protons, with negatively charged electrons orbiting around it. Protons normally stay put in the nucleus, but electrons can move from atom to atom, allowing them to flow through materials, such as metals, that conduct electricity. A place with an excess of electrons over protons will have a negative charge; a place with a deficit will have a positive charge. Since opposite charges attract one another, electrons will flow from a negatively charged area to a positively charged one if allowed to do so, creating an electric current.

Using Electrical Energy

Electricity is useful both in itself and as a means of transferring energy over long distances. It is essential to various industrial processes, telecommunications and the Internet, computers, televisions and many other devices in common use. It can also be converted into other forms of energy for use in a variety of other applications.

When an electric current flows through a conductor, it generates a certain amount of heat. The amount generated depends on how well the material conducts electricity. A good conductor, such as copper, produces very little. For this reason, copper wires and cables are commonly used to transmit electricity: when heat is produced, energy is lost, so a good conductor minimizes energy loss. Materials that conduct electricity less well produce more heat, so they tend to be used in electric heaters, cookers and ovens, for example.

Electrical energy can also be converted into light. Early arc lights depended on an electrical discharge across a small gap to heat the air to the point where it glows — the same principle as lightning. Later, the filament light bulb was introduced: this relies on the current causing a thin, coiled wire to glow white-hot. Modern, energy-saving light bulbs pass a high voltage current through a thin gas, causing it to emit ultraviolet light, which strikes a fluorescent coating to produce visible light.

When a conducting material, such as a copper wire, is moved in a magnetic field, a current is generated. Conversely, a current flowing through a wire will, if it experiences a magnetic field, produce movement. This is the principle behind an electric motor. These devices consist of an arrangement of magnets and coils of copper wire such that when a current flows through the wire, a turning motion is produced. Electric motors are widely used in industry and in the home, for example in washing machines and DVD players.

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Measuring Electrical Energy

Energy is measured in joules, a term named after the physicist James Prescott Joule. One joule is roughly the amount of energy required to lift a one pound (0.45 kilogram) weight a vertical distance of nine inches (22.9 cm). It is, however, usually more convenient to think of electricity in terms of power, which is energy divided by time, or the rate at which it flows. This gives the possibly more familiar unit of the watt, named after the scientist James Watt. One watt is equivalent to one joule per second.

There are a number of other units that relate to electricity. The coulomb is the unit of electrical charge. It can be regarded as a quantity of electrons — 1.6 x 1019 — since all electrons have the same, very small, charge. The ampere, usually abbreviated to “amp”, is the unit of electric current, or the number of electrons that flow in a given amount of time. One amp is equivalent to one coulomb per second.

The volt is the unit of electromotive force, or the amount of energy that is transferred per unit of charge, or coulomb. One volt is equivalent to one joule of energy being transferred for each coulomb of charge. Power, in watts, is equivalent to volts multiplied by amps, so a five amp current at 100 volts would be equivalent to 500 watts.

Generating Electrical Energy

Most electricity is generated by devices that convert rotational motion into electrical energy, using the same principle as an electric motor, but in reverse. The movement of coils of wire within a magnetic field produces an electric current. Commonly, heat, often generated by the burning offossil fuels, is used to produce steam that powers a turbine to provide the rotational motion. In a nuclear power plant, nuclear energy provides the heat. Hydroelectric power uses the movement of water under gravity to drive the turbine.

The electricity generated at power plants is generally in the form of alternating current (AC). This means that the current is constantly reversing its direction, many times per second. For most purposes, AC works well, and this is how electricity reaches the home. Some industrial processes, however, require direct current (DC), which flows in one direction only. For example, the manufacture of certain chemicals uses electrolysis: the splitting of compounds into elements or simpler compounds using electricity. This requires direct current, so these industries will either require AC to DC conversion or will have their own DC supply.

It is more efficient to transmit electricity through power lines at higher voltages. For this reason, generating plants use devices called transformers to increase the voltage for transmission. This does not increase the energy or power: when the voltage is raised, the current is reduced and vice versa. Long distance transmission of electricity takes place at many thousands of volts; however, it cannot be used in homes at these voltages. Local transformers reduce the voltage to around 110 volts in the USA, and 220-240 volts in Europe, for domestic supplies.

Electricity for small, low power devices is often supplied by batteries. These use chemical energy to generate a relatively small electric current. They always generate a direct current, and therefore have a negative and a positive terminal. Electrons flow from the negative to the positive terminal when a circuit is completed.


Source / Courtesy : WiseGeek

What is Database?

A database is a collection of information that is organized so that it can easily be accessed, managed, and updated. In one view, databases can be classified according to types of content: bibliographic, full-text, numeric, and images.

In computing, databases are sometimes classified according to their organizational approach. The most prevalent approach is the relational database, a tabular database in which data is defined so that it can be reorganized and accessed in a number of different ways. A distributed database is one that can be dispersed or replicated among different points in a network. An object-oriented programming database is one that is congruent with the data defined in object classes and subclasses.

Formally, a “database” refers to a set of related data and the way it is structured or organized. Access to this data is usually provided by a “database management system” (DBMS) consisting of an integrated set of computer software that allows users to interact with one or more databases and provides access to all of the data contained in the database (although restrictions may exist that limit access to particular data). The DBMS provides various functions that allow entry, storage and retrieval of large quantities of information as well as provide ways to manage how that information is organized.

Because of the close relationship between them, the term “database” is often used casually to refer to both a database and the DBMS used to manipulate it.

Outside the world of professional information technology, the term database is often used to refer to any collection of related data (such as a spreadsheet or a card index). This article is concerned only with databases where the size and usage requirements necessitate use of a database management system.

Existing DBMSs provide various functions that allow management of a database and its data which can be classified into four main functional groups:

  • Data definition – Creation, modification and removal of definitions that define the organization of the data.
  • Update – Insertion, modification, and deletion of the actual data.
  • Retrieval – Providing information in a form directly usable or for further processing by other applications. The retrieved data may be made available in a form basically the same as it is stored in the database or in a new form obtained by altering or combining existing data from the database.
  • Administration – Registering and monitoring users, enforcing data security, monitoring performance, maintaining data integrity, dealing with concurrency control, and recovering information that has been corrupted by some event such as an unexpected system failure.

Both a database and its DBMS conform to the principles of a particular database model. “Database system” refers collectively to the database model, database management system, and database.

Physically, database servers are dedicated computers that hold the actual databases and run only the DBMS and related software. Database servers are usually multiprocessorcomputers, with generous memory and RAID disk arrays used for stable storage. RAID is used for recovery of data if any of the disks fail. Hardware database accelerators, connected to one or more servers via a high-speed channel, are also used in large volume transaction processing environments. DBMSs are found at the heart of most database applications. DBMSs may be built around a custom multitasking kernel with built-in networking support, but modern DBMSs typically rely on a standard operating system to provide these functions. Since DBMSs comprise a significant economical market, computer and storage vendors often take into account DBMS requirements in their own development plans.

Databases and DBMSs can be categorized according to the database model(s) that they support (such as relational or XML), the type(s) of computer they run on (from a server cluster to a mobile phone), the query language(s) used to access the database (such as SQL or XQuery), and their internal engineering, which affects performance, scalability, resilience, and security.

How Should I Prepare for Lightning Storms?

Lightning storms, severe storm systems that produce frequent cloud-to-ground lightning strikes, can cause serious damage to structures, trees, power lines and consumer electronics. They may trigger fires or damage tree limbs, which in turn can cause even more structural damage. When local weather stations warn of impending lightning storms, there are a number of actions a person should take in order to protect his or her life and property. People and animals should be moved inside, if possible, away from windows. Electronics should be unplugged so there is no chance of them being damaged by power surges.

People and pets should go inside homes and buildings during lightning storms to the avoid risk of getting struck.


One important step to take before lightning storms arrive is to move all living things indoors. Pets, livestock, and family members all need to be under enough shelter to remain dry, warm, and protected from the elements. Standing under the tallest object in an open area, such as a tree at a golf course, is never a good idea, however. Lightning tends to strike the highest point that will lead the electrical charge to the ground. A covered picnic pavilion or the inside of a car would be much safer during lightning storms than a tree or open field.

The same precautions a person should take for any severe weather event apply to lightning storms. A weather radio with a battery back-up should be turned on for regular updates on the storm’s location and intensity. Candles or battery-powered lamps should be readily available in case of a power failure. Family members should remain in lower levels of the home and stay away from windows. Strong lightning storms often put down significant numbers of lightning strikes and loud thunder, so younger children and pets may need extra attention until the storm subsides.

Many people who own consumer electronic devices such as home computers, stereo systems, DVD players and so on should already have those devices plugged into a power strip featuring surge protection, but there are those who don’t. During lightning storms, a direct lightning strike on a nearby power line can cause a temporary surge in electrical power entering the home’s outlets. A surge protector should automatically detect and filter this extra energy, but appliances plugged directly into unprotected sockets can suffer damage. Before a lightning storm arrives, a person should completely unplug all unnecessary electrical appliances and electronic equipment not protected by a surge protector.

It's best to stay away from standing water, such as an ocean or lake, during lightning storms.
It’s best to stay away from standing water, such as an ocean or lake, during lightning storms.


Some home owners invest in lightning grounding systems in order to protect their property during a lightning storm. If a lightning bolt does strike the house, a grounding wire will draw the electrical energy away and into a remote part of the property. The installation of a properly grounded lightning rod can also discourage lightning from striking the roof or a nearby tree.

Fortunately, most lightning storms leave distinctive images on modern weather radar systems, so meteorologists can generally warn viewers of a dangerous storm’s predicted path and intensity. Some radar systems can even detect individual lightning strikes within a storm systems and warn specific areas of the potential for danger. The time to take precautions is long before the actual arrival of the storm, however. Once lightning begins to hit an area, it may be too late to save electronic equipment from receiving damage.

If a driver cannot find suitable shelter or drive out of a dangerous storm system, remaining in the car would not be a bad idea. A car will act as a Faraday cage during a lightning strike, meaning the electrical energy would be directed around the car’s exterior, but occupants would remain safe and insulated. The main goal during a strong lightning storm is not to be the tallest target in the area and to stay away from natural conductors such as standing water or metal fences.

Hail can accompany lightning storms.
Hail can accompany lightning storms.
Faraday cage with bolt of electricity.
Faraday cage with bolt of electricity.
An especially heavy layer of cirrus can indicate an incoming storm system.
An especially heavy layer of cirrus can indicate an incoming storm system.
A lightning rod can help protect a building from lightning strikes.
A lightning rod can help protect a building from lightning strikes.

What Is an Electric Current?

Electric current is measured using an ammeter.
Electric current is measured using an ammeter.

Electric current is the name for the flow of electrons that makes up the movement of electric charge. Current flows when the voltage on one end of a conductor differs from the voltage on the other end of a conductor. A force that most people deal with nearly every day, flowing current includes lighting, electrical power cords, and the surprising shock that comes from shuffling shoes on carpet in dry weather. This force is measured in units called amperes, also called amps.

A ubiquitous presence in modern life, current can be found flowing through conductors. Conductors include metal like aluminum, copper, and steel, but water can also conduct current. Electric current has proved to be quite useful to people, but it can also pose a danger to life and property. As humans are made up largely of water, this means that they can conduct current as well, which puts them at risk for electric injury if they come into contact with a conductor with an electric charge. They can also be injured if they are in contact with a body of water when it has a charge, even if the water is in the form of a small stream or puddle.

When referring to electric current, it is proper to say that the current flows through a conducting object like a wire or appliance, not in it. Insulation like rubber or ceramic is commonly used to keep current from flowing into nearby conductors. While air acts as insulation for wires that do not have contact with conductors, open-air wires must often be insulated at connecting points like transformers or building entry and exit points.


An ampere, or amp, is the standard unit used to measure electric current. On paper, amperes can be calculated from coulombs by dividing the coulombs by one second. Amperes in electric current are measured using a tool called an ammeter. In equations, electric current is often referred to as I, which is used to stand for the intensity of current before the term was shortened to electric current.

Lightning is a form of electric current.
Lightning is a form of electric current.

Electric current can cause fire. When it comes in the form of lightning, this force can set fire to foliage and damage buildings. To prevent lightning damage to buildings in areas prone to lightning storms, building owners often install devices called lightning rods that attract the lightning charge to a high metal rod, which redirects and dispels the current underground. Desert electrical storms that produce lightning with no rain can set fire to dry brush that can grow to damage many homes and acres of land.

Voltage measures the energy that is carried by an electric charge. Voltage is measured in volts. The flow of electricity is often compared to the flow of water, and voltage is the electric equivalent of water pressure. The higher the voltage, the faster electrons will flow through the conductor.

Source / Courtesy : WiseGeek

What is Ohm’s Law?

German physicist Georg Ohm uncovered how a material's make up, length and thickness influences how much current will flow through it at a certain voltage.
German physicist Georg Ohm uncovered how a material’s make up, length and thickness influences how much current will flow through it at a certain voltage.

Ohm’s Law is a law used in physics that basically explains how electricity operates properly within a simple circuit. In order to explain the electrical process, the law shows how the three elements of electricity — ampere, resistance, and voltage — work together to create a functioning electrical circuit. The law states that the amount of electrical current, measured in amperes, traveling through a conductor is proportional or equal to the voltage, but is inversely proportional to the resistance in the conductor.

The proponent and the namesake of the law was George Simon Ohm, a renowned German physicist in the early 1800s. While working as a professor at the Jesuit Gymnasium of Cologne in Germany, he experimented with and observed the behavior of electricity in simple circuits with different wire lengths. He described and documented all the results in a book, “The Galvanic Circuit Investigated Mathematically,” which was initially rejected but later acknowledged, leading to the establishment of the Ohm’s Law.

Ohm’s Law can be written in a simple mathematical equation: I = V/R, where I is for the electrical current measured in amperes, V is for the voltage, and R is for the resistance. In this equation, the resistance is usually a constant variable, since its value is not dependent on the amount of electric current, but rather on the materials used to make the circuit, such as the metal wires and the resistor itself. The formula can be expressed in other inversed forms such as V = IR, or R = V/I. These inversed formulas can help find the value of one element if the values of the two other elements are already identified.

There are essentially three “truth” statements that one should remember regarding Ohm’s Law. The first statement is that the value of I will increase or decrease if the value of V increases or decreases, respectively. The second statement is that the value of I will decrease if the value of R increases and the value of V does not change. The third statement is that the value of I will increase if the value of R decreases and the value of V remains the same.

Ohm's Law can be used to find the electrical resistance applied to a circuit by resistors.
Ohm’s Law can be used to find the electrical resistance applied to a circuit by resistors.


The principle of Ohm’s Law can be practically applied in appliances and any equipment operated by electricity or a battery. For example, a simple light-emitting diode (LED) needs only 2 volts and .02 amperes to light up, but is connected to a 6-volt battery. This may cause the LED to short circuit, and a resistor is needed to reduce the current. Using the formula R = V/I, one can determine that a resistor containing 200 ohms is needed to control the current coming into the LED.


Source / Courtesy : WiseGeek

Get an Understanding of Computer Terms

If you’re upgrading your PCs, you might run into many IT terms and computer-related words and phrases that are difficult to understand. We’re to help you know what you’re getting!


Also known as ‘chip’ or ‘CPU’, the processor controls everything your computer does. It lets you do several things like work, email and surf – all at the same time. More powerful processors are better for more demanding tasks so get one that performs a little above your current needs.



The computer uses random access memory (RAM) to process what the user is doing as they are doing it. This includes multitasking, writing a letter, editing a photo or browsing a web site. 4GB of RAM should be enough for most of your everyday needs, and you can always upgrade and add more RAM later.

Hard Drive

Think of the Hard Disk Drive (HDD) as your computer’s long-term memory. It acts as a filing cabinet for your documents, data, media files and so on. The size or capacity of a hard drive is measured in gigabytes. If you plan on storing a lot of videos and other big files, get a larger hard drive. Another option is to purchase an external USB 2.0 hard drive. Some new notebook PCs now use solid-state drives (SSD) with no moving parts, making them more resistant to shock, quieter and with faster information access.

Processor Number

Acting like a serial number, the processor number differentiates features within a processor family, with a higher number generally indicating more features. You can use this number to verify that your chosen processor includes the features you want. Keep in mind that processor numbers do not work across different processor families.

Intel® HD Graphics

Available as a built-in visual feature on selected Intel® Core™ processors, Intel® HD Graphics enables discrete 3D graphics performance without the added cost of a separate graphics card. You’ll enjoy crisp images with the highest frames per second for mainstream videos.00612012015

Intel® Quick Sync Video

Intel® Quick Sync Video accelerates hardware performance during video editing, burning and sharing to significantly reduce waiting time from hours to just minutes.

Intel® InTru™ 3D Technology

Watch Blu-ray videos in stereo 3D and full 1080p resolution on your computer with Intel® InTru™ 3D Technology.

00712012015Intel® Turbo Boost Technology 2.0

A feature available on selected 4th gen Intel® Core™ processors, Intel® Turbo Boost Technology 2.0 automatically provides an even greater boost of speed to reduce lag time to meet the heavy processing demands of high-end apps.

Integrated Graphics

A graphics component needed to view images. Integrated graphics offers the performance for everyday tasks like watching HD videos, viewing photos and creating presentations. Standard in selected Intel® Core™ processors, integrated graphics improve graphics performance and notebook battery life.

Intel® Clear Video Technology00812012015

Intel® Clear Video Technology delivers higher visual performance for sharper images, richer colour and superior audio and video playback.

Intel® Wireless Display

This built-in visual feature allows you to wirelessly view your personal content, online TV programmes, films and videos on your home TV screen.

00912012015Clock Speed

Just like a stopwatch, clock speed measures how fast your processor performs one activity cycle. A faster clock speed enables your computer to execute instructions more quickly, benefitting most applications from spreadsheets to video editing and more. Clock speed rates are shown in gigahertz (GHz). (See GHz)

Gigahertz (GHz)

A unit to measurement commonly used to express processor speed, also referred to as clock speed. 1 Gigahertz (GHz) = 1 billion cycles per second. A higher number used to mean a faster processor, but advances in technology have made chips more efficient. For this reason it’s not advisable to compare performance based on GHz or clock speed alone. (See Clock Speed)

nm (nanometre)

A unit of measure, a nanometre (nm) is one-billionth of a metre. The transistors on Intel’s latest processors are just 32nm wide, with older models at 45nm and 65nm. The smaller size allows transistors to be packed more densely, leak less energy, produce less heat and switch faster, so processors run faster, use less power and are more energy-efficient.

Intel® Hyper-Threading Technology

Available on selected Intel® processors, Intel® Hyper-Threading Technology makes more efficient use of your processor so you can run demanding applications while maintaining system responsiveness. With this technology, multimedia enthusiasts can create, edit and encode heavy graphics files while running other applications, without losing performance.

Cores and Threads01012012015

Cores and threads go hand-in-hand. Multi-core processors are single chips that contain two or more distinct processors or execution cores in the same integrated circuit. Multi-threading allows each core to work on two tasks at once, letting you do more things at the same time for faster results.

Built-In Visuals

A group of technology features designed to enhance the visual experience delivered by the Intel® Core™ processors. Built-in visual features include Intel® Quick Sync Video, Intel® HD Graphics, Intel® Clear Video Technology and Intel® InTru™ 3D Technology.

Discrete Graphics

This graphics component comes as an additional graphics card. While ideal for high-end 3D designers and video editors, it doesn’t add much performance for most business users. It’s important to note that only more powerful processors can make full use of discrete graphics.

Intel® Smart Cache

A cache is a fast storage area where the processor keeps frequently accessed data. Intel® Smart Cache maximises this data storage. It allows each processor core to utilise up to 100% of the space and pull data faster, improving overall performance for rich media applications and games.


Understanding Wi-Fi Speeds


Wi-Fi speeds are designated by letter, not by number. Unlike the easy to translate number-as-network-speed designation we find with Ethernet the Wi-Fi designations actually refer to the draft versions of the IEEE 802.11 networking standard that dictates the parameters of the Wi-Fi protocol.

802.11b was the first version widely adopted by consumers. 802.11b devices operate at a maximum transmission of 11 Mbit/s but the speed is highly dependent on signal strength and quality—realistically users should expect 1-5 Mbit/s. Devices using 802.11b suffer from interference from baby monitors, bluetooth devices, cordless phones, and other 2.4GHz band devices.

802.11g was the next major consumer upgrade and boosted the max transmission to 54 Mbit/s (realistically about 22 Mbit/s accounting for error correction and signal strength). 802.11g suffers from the same kind of 2.4GHz band interference that 802.11b does.

802.11n is a significant upgrade to the Wi-Fi standards—devices use multiple-input multiple-output antennas (MIMO) to operate on both the 2.4GHz and relatively empty 5GHz bands. 802.11n has a theoretical maximum of 300 Mbit/s but accounting for error correction and less than ideal conditions you can expect speeds in 100-150 Mbit/s range.

802.11ac is a huge upgrade that brings wider channels (80 or 160 MHz versus 40 MHz), more spatial streams (up to eight) and things like beamforming, which sorta send the waves directly to your device instead of bouncing all around, making things much faster. How much faster? There are some models that can do one gigabit per second. It’s extremely fast.

Like Ethernet, Wi-Fi speeds are limited by the weakest link in the direct network. If you have an 802.11n capable Wi-Fi router but your netbook only has an 802.11g capable Wi-Fi module you will max out at the 802.11g speeds. In addition to the speed limitations there is a very pressing reason for abandoning the oldest popular Wi-Fi protocol 802.11b. You must use the same level of encryption on every device in your network and the encryption schemes available to 802.11b devices are weak and have been compromised (WEP encryption, for example, can be compromised in a matter of minutes by a moderately skilled child). Upgrading your Wi-Fi router and wireless equipment allows you to upgrade your wireless encryption as well as enjoy faster speeds. If you haven’t done anything to secure your router now would be a good time to read our guide to locking down your Wi-Fi network against intrusion.

Also like Ethernet, upgrading to the maximum speed—in this case 802.11n—is best suited for people moving large files and streaming HD video. Upgrading to 802.11n will have a negligible impact on your web browsing speed but will have an enormous impact on your ability to wirelessly stream HD content around your home.

What is a Customized SBC?

SBC – Single Board Computers

SBCs are off-the-shelf products that can be used to develop end-products or applications for a variety of industries. SBCs come along with integrated software and hardware, which includes SoC, memory, power requirements, real world multimedia and connectivity interfaces such as USB, UART, CAN, HDMI, Ethernet, SDIO, MMC, Analog Audio, display etc. The SBC approach helps system developers to focus on the application specific parts. An extensive range of SBCs based on a variety of microprocessors, memory sizes, supported interfaces and operating systems such as Windows Embedded Compact, Linux, Android etc. are available in the embedded market. This offers flexibility to the users to choose the appropriate SBC based on their cost, features and performance requirements. Low cost SBCs are widely used in academic research projects and in feature specific end-products.


However, the SBC approach suffers inherently from various drawbacks. First of all, the SBC approach leads to high switching cost to migrate to future technologies. As SBCs comes in standard sizes and real world interfaces, so it is difficult to accommodate future improvements in technology and thus the OEMs need to switch to an entirely new SBC solution. Secondly, customizing a SBC is cumbersome as the processor chipset and surrounding I/O are closely coupled due to the single-board design. Finally, space constrained applications may also struggle to use the standardized SBC available in the market.

The Computer On Module (COM) or System On Module (SOM) coupled along with a baseboard offers an equivalent solution as that of the SBCs. The COM approach separates the complex microprocessor part from the relatively simple I/O part and thus offers flexibility to customize the baseboard part based on the feature and size requirements of the end-product. Furthermore, pin-compatible modules ensure convenient and cost effective way to migrate to future technology.

A Customized SBC is an off-the-shelf embedded solution that is a combination of a COM/ SOM and a carrier board. This combination provides a desirable alternative to SBCs in developing any embedded end-products as the former offers the flexibility and scalability inherent to the COM approach and yet, is a ready-to-use complete embedded solution, one of the main benefits of the SBC approach.

Windows CE
Touch Support






What is a Computer-On-Module?

A Computer-On-Module (COM) / System On Module (SOM) is a highly integrated embedded computing solution that can be used to design and develop end-products for a variety of industries . The COM/SOM approach offers flexibility to system developers to focus on application development by using an off-the-shelf module that has the generic hardware and software to develop any application. This approach greatly reduces the time-to-market and development cost.

COM/SOM are generally built around microprocessors, system-on-chips, or microcontrollers. They integrate additional devices and peripherals which are needed to realise a fully functional computer, which normally includes RAM, non-volatile storage and power supplies.

They are essentially another layer of abstraction that sits above the SoC (System-on-Chip) concept, providing further integration in areas of hardware and software that are not application specific, but are application agnostic.

  • Optimized for Multicore
  • High-Speed Multimedia Interfaces (PCIe, SATA)
  • Direct Breakout™ for Easy Baseboard Routing
  • Fully Compatible Product Family
  • Small Form Factor
  • Free Support Directly from the Developers
  • 10+ Years Product Lifecycle

Carefully view the following image for the big picture 🙂

What is a Resistor?

Ads by Google Variable Resistor 5 Ohm Resistor Resistor High Voltage Resistor Component Electrical Resistor Series Resistor Resistor Values Standard Resistor Resistor Types Chip Resistors Resistor Calculator Resistor Color A resistor is an electronic component that can lower a circuit’s voltage and its flow of electrical current.
A resistor is an electronic component that can lower a circuit’s voltage and its flow of electrical current.

A resistor is a component of a circuit that resists the flow of electrical current. It has two terminals across which electricity must pass, and it is designed to drop the voltage of the current as it flows from one terminal to the other. Resistors are primarily used to create and maintain known safe currents within electrical components.

Resistance is measured in ohms, after Ohm’s law. This law states that electrical resistance is equal to the drop in voltage across the terminals of the resistor divided by the current being applied. A high ohm rating indicates a high resistance to current. This rating can be written in a number of different ways — for example, 81R represents 81 ohms, while 81K represents 81,000 ohms.

The amount of resistance offered by a resistor is determined by its physical construction. A carbon composition resistor has resistive carbon packed into a ceramic cylinder, while a carbon film resistor consists of a similar ceramic tube, but has conductive carbon film wrapped around the outside. Metal film or metal oxide resistors are made much the same way, but with metal instead of carbon. A wirewound resistor, made with metal wire wrapped around clay, plastic, orfiberglass tubing, offers resistance at higher power levels. Those used for applications that must withstand high temperatures are typically made of materials such as cermet, a ceramic-metal composite, or tantalum, a rare metal, so that they can endure the heat.

Electrical resistance was discovered by German physicist Georg Ohm in the 19th century and has since been measured in ohms
Electrical resistance was discovered by German physicist Georg Ohm in the 19th century and has since been measured in ohms


Resistors are coated with paint or enamel, or covered in molded plastic to protect them. Because they are often too small to be written on, a standardized color-coding system is used to identify them. The first three colors represent ohm value, and a fourth indicates the tolerance, or how close by percentage the resistor is to its ohm value. This is important for two reasons: the nature of its construction is imprecise, and if used above its maximum current, the value can change or the unit itself can burn up.

Every resistor falls into one of two categories: fixed or variable. A fixed resistor has a predetermined amount of resistance to current, while a variable one can be adjusted to give different levels of resistance. Variable resistors are also called potentiometers and are commonly used as volume controls on audio devices. A rheostat is a variable resistor made specifically for use with high currents. There are also metal-oxide varistors, which change their resistance in response to a rise in voltage; thermistors, which either raise or lower resistance when temperature rises or drops; and light-sensitive resistors.

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[lightbox full=”http://wingedpost.org/wp-content/uploads/2014/10/01028102014.jpg” title=”Resistors are electrical devices that manage the flow of current through a circuit.”]Resistors[/lightbox]
[lightbox full=”http://wingedpost.org/wp-content/uploads/2014/10/00828102014.jpg” title=”A variable resistor is able to manage flows of electricity at a specific level as well as below that level.”]Variable Resistor[/lightbox]
[lightbox full=”http://wingedpost.org/wp-content/uploads/2014/10/00928102014.jpg” title=”Variable resistors can be adjusted to change the level of resistance.”]Level of Resistance[/lightbox]


Source / Courtesy : WiseGeek