Science

The brachial plexus consists of nerve fibers between C5 and T1. Learning the pathway of each of these nerves can be difficult, but a simple trick makes it much easier.

A function relates variables by taking the value of an independent variable as a sort of "input" and returning a single value for the dependent variable, or "output." By its definition, a...

Chemical kinetics is the study of chemical reactions and their rates. It includes experimental conditions that speed up reaction rates and favorably affect an intermediate "Transition State." It...

Containing a universal indicator, pH paper is paper that can be defined as the product used to determine acidity levels of solutions.

The Celsius temperature scale was invented by Anders Celsius (1701-1744), a Swedish astronomer. It is also called the centigrade scale, since each degree is equal to 1/100 of the difference...

A fluorescent light bulb is a complicated but efficient device that takes advantage of the nature of electricity and the properties of a number of chemical substances. The design brings these...

Many tools are available for hobbyists who want to make their own printed circuit boards (PCBs). One of the simplest methods uses a laser printer. You create the PCB pattern using software, print...

Titration is a method used to determine the concentration of a compound in solution. A compound in a solution of known concentrate is added to the unknown solution. The two compounds react, and...

Acetate (CH3COO-) is the conjugate base of acetic acid (CH3COOH), the acid associated with vinegar. The acetate ion is composed of two carbon (C) atoms, three hydrogen (H) atoms, and two oxygen...

The compass rose has existed in some form ever since humans discovered magnetic rock. The first compasses weren't compasses at all, but magnetized metal rods with one end designated to point...

Transducer is a device that converts one form of energy into another. Many transducers convert electric waves into mechanical vibrations---or vice versa. Loudspeakers, microphones and phonograph...

Halogen light bulbs can replace your normal household bulbs in fixtures and lamps with a brighter and more efficient light. But halogen lights have far more uses whenever an intense light is needed.

Two hydrogen atoms are covalently bonded to an oxygen molecule in water. When the covalent bonds in the water molecule are broken, the hydrogen atoms combine to produce hydrogen gas, and the...

A crane is a pulley system used to move very heavy loads both vertically and horizontally. They are a vital part of skyscraper construction, because they are the only devices capable of moving up...

Whether you're looking for a fun craft project to do with the kids or searching for a new way to view the world around you, making a cheap telescope can be a great way to see things from a fresh...

Although the initial investment in a home energy system can cost about the same as a new car, it immediately begins paying for itself by lowering utility bills significantly immediately and over...

Electrical conductivity is a complex, yet fundamental principle of electricity. It occurs unseen on an atomic level, yet it is the driving force behind our modern industrialized society.

Zinc plating is done for a number of reasons, often for practical surfacing and sometimes for decorative purposes. Many times, things such as screws and car parts are plated with zinc during...

One of the primary principles in the study of statics and dynamics, particularly in fluids, is the conservation of mass. This principle states that mass is neither created nor destroyed. In...

A relay is an electromechanical device that uses a control voltage to operate a switch to either open a connection or close one. Electric and electronic equipment use relays for a wide variety of...

The fossil fuel coal has been used as an energy source for heat and cooking for more than 400 years. Its main use today is in the production of electricity, but that use is slowly giving way to...

Mosses are most recognizable as the green carpet that covers a forest's moist floor. They are part of the bryophyte family, and like the related hornworts and liverworts are some of the earliest...

There are two primary properties of air that can be measured: flow and pressure. Barometers measure pressure, while there are several different techniques you can use to measure flow. Chemical...

Sound travels through air as waves of increasing and decreasing changes in the pressure of the air. The number of complete sound waves moving past a point is called the frequency, which is...

An electrical relay is an electromechanical device operated by a small amount of electricity to control a larger amount of electricity. Relays are used for both control and safety.

Relays use a small amount of electricity to control a larger amount of electricity. A choice of whether to use a solid-state relay or a mechanical one will depend on your application and price range.

Solar ovens use the heat of the sun to cook food. This solar oven can be built in just a few minutes using a pizza box and everyday items found around the house or in a local grocery store. The...

Sound waves, ocean waves, alternating current, and electromagnetic waves such as light and X-rays occur in regular repeating cycles. One measure of these events is the number of times the event...

Hertz (Hz) is a unit of measure that denotes the number of times an event occurs in one second. This measurement is commonly employed in measuring the frequency of periodic motion or periodic waves.

A cell---often referred to as the building block of life---is the basic functional unit of all living organisms, including human beings. Each cell can reproduce by cell division, metabolize energy...

Although not visible, infrared light is vital to most living organisms on planet Earth. People experience infrared light when being warmed by the sun and using a remote control.

Almost all electrical power systems use relays for control and safety. Without them, safe control of power would be impossible, whether it's a small system for personal use or an electric plant to...

One of the ways inventions come to be is when someone is doing a task and realizes there has to be a better way to do it. She might improve on an instrument or tool that is already in use or come...

Maps are used to represent a larger area in a scaled-down format so people can get a birds' eye view of the area. The map scale shows how the distance on the map compares to the distance in real...

Printed circuit boards are sheets of fiberglass or other material embedded with electrical conductors. Conductive pads allow electrical components to be soldered in place. Circuit boards are found...

Alloys have played a significant role in the development of human civilization. We have even named periods of human history, such as the Bronze Age, after major alloy developments. Alloy...

A ballast is a type of electronic regulator used to regulate the flow of electricity in normal and compact fluorescent light bulbs. Fluorescent bulbs do not use a filament like the incandescent...

You can make a simple hand-cranked, alternating-current generator with magnets, wire, a nail and some cardboard. The basis of an A/C generator is to cut the magnetic field lines of magnets with...

Cisco-Eagle, a manufacturer of conveyor systems, says that "the standard speed for most unit handling conveyors is 65 FPM (Feet Per Minute). This is the average speed a person walks when carrying...

Wet-test laboratory methods include gravimetric (by weight) and volumetric (solution-based) determinations. Of the two methods, gravimetric analysis is the more accurate. In many instances,...

Many things, like houses and buildings, are described in terms of square feet. When someone says a building has three acres of floor space, you might wonder how they sized the building and...