Science

Direct sunlight is important in the natural world and elsewhere because it provides the energy which fuels the growth of plants that are necessary for the survival of all life forms on the planet.

Hurricanes are tropical cyclones. West of the International Date Line, the storms are known as typhoons. They are called cyclones in Australia and India. Heat causes the condensation of ocean...

Respiration is a process of gas exchange and energy conversion. It is the act by which we take in oxygen, expel carbon dioxide and convert food energy into chemical energy in our cells. We breathe...

Sound travels as pressure waves through the air. Sound insulation is the resistance to sound; in this case, insulation material reflects the waves. Sound absorption converts the sound to energy or...

As the world's population continues to grow, and with the economies in developing countries expanding rapidly, there is a greater demand for energy than at any other time in human history. In...

The pulse energy of a laser is total energy contained in a single laser pulse.

A steam turbine is a mechanical device whose purpose is to convert thermal (or heat) energy into work. Thermal energy is the type of energy that manifests itself as an increase in temperature. The...

Before an object begins moving, it has an amount of potential energy. Once that objects begins to gain motion, that potential energy converts into kinetic energy. Calculating this equation doesn't...

Energy, usually generated in the form of electricity, can be drawn from a number of sources. These include different types of finite natural resources drawn from the earth, as well as renewable,...

Wind energy is mechanical or electrical energy generated by harnessing the power of the wind. According to the U.S. National Renewable Energy Laboratory, one of the earliest devices to harness...

Dextrose is another word for D-glucose (or dextrorotatory glucose), a sugar used for energy by most living organisms. The term "dextrose" is commonly used in the food industry.

Perpetual motion is a theoretical notion that drives inventors to attempt to create machines that continue on forever. But creating a perpetual motion machine is impossible.

In the atomic world, heat can be equated with energy. Some elements give off energy very well--they are good conductors. Others are very poor at giving off energy--they are good insulators. Since...

Wind turbines are used to capture wind and convert the kinetic energy (energy generated through motion) into mechanical or electrical power. Most turbines are used in wind farms to generate bulk...

Solar energy collectors have been in common use since the 1890s. A solar collector in a sunny spot has been used to heat water or make electricity. The limitation has always been times when the...

The compressor is one of the most important parts of the air conditioning system. Air conditioners work using the laws of thermal energy and heat transfer. The medium by which heat is moved around...

Flywheels have many uses in modern machinery. Probably the most common is to store rotational energy to help drive internal combustion engines. The engine spins a flywheel mounted at the...

During photosynthesis, "producers" like green plants, algae and some bacteria convert light energy from the sun into chemical energy. Photosynthesis produces chemical energy in the form of...

Nuclear and solar power are products of quantum physics. Instead of the smooth, continuous, predictable world we're familiar with, quantum physics is a realm of discrete bundles of matter and energy.

The resistance of a wire refers to the ease at which current is able to flow through it. A wire with a higher degree of resistance will not perform as efficiently as a wire with less resistance.

With all of the attempts to come up with cheap, dependable energy, tidal generators have been receiving a lot more attention than they have in the past from the public and from the engineering...

When speaking about cell balance, it is common to run into the term "homeostasis." A cell must maintain homeostasis, literally a permanent condition where everything remains the same. For a cell,...

Earth has given us many resources that allow us to survive. We make use of renewable (like sun and air) and nonrenewable (like minerals) resources. Water is one of the main resources we use and...

A primary source of energy is any source of energy found in nature that has not been converted. Different primary sources of energy are used in different regions of the world for a variety of...

Energy is necessary to power many items that people normally use, including appliances, lighting, and vehicles. Energy sources can be classified as renewable (able to be recreated repeatedly) or...

Wave motion arises from the shifting of energy. That energy may be in a photon, in a water wave or a solid medium. It can be from oscillation between stored energy and kinetic energy, or strictly...

The term "greenhouse effect" refers to the presence of gases in the Earth's atmosphere that trap the sun's energy and increase the planet's temperature as a result. Examples of greenhouse gases...

As you plug along through your chemistry class, you're bound to run into the concept of (gasp!) electron configuration. What's that supposed to mean and how the heck do you find the electron...

Recycling saves energy primarily because it reduces the need to extract and refine natural resources. For many materials, the energy to recycle is less than the energy needed to make it from...

A cold soft drink on a hot day can be very refreshing; keeping that soft drink cold on a hot day can be quite challenging. In the past, soft drinks were packaged exclusively in glass bottles....

Solar energy has been harnessed by humans for thousands of years for heating purposes, and more recently for electricity generation. Solar power is an extremely vast resource, but it has some...

A kilowatt-hour is an electrical unit of energy. It is the amount of work done when 1 kilowatt is expended or consumed in an hour. Power stations that supply electricity to buildings use...

Solar energy comes from the sun and travels through outer space to the earth. Solar energy comes in the form of light, and when the light comes to planet Earth, sometimes the solar energy is...

Laser eye surgery refers to a handful of refractive eye surgeries that use powerful lasers to alter the shape of the cornea. The goal of refractive eye surgery (be it laser-assisted or otherwise)...

Every chemical reaction starts with one or more reactants. Atoms, molecules or free electrons can participate. They combine, swap atoms or decompose into the reaction's products. If a reactant is...

Thermodynamics arose out of the observations that steam engines produced heat and were not entirely efficient. In the 19th century, scientists articulated three laws of thermodynamics, which...

The term "living" can describe either a single or a multitude of organisms that make up a larger organism. Living organisms have evolved and adapted to their environments for billions of years,...

Chemical heat packs can be used to apply heat to specific areas on the body to help with pain and injury recovery. They are most popular in sporting events where athletes suffer from various...

The natural world is awash in sound. This is even more true of the man-made world. Whenever an object sends out vibrations you can hear, that is, between 20 and 20,000 cycles per second, it...

The periodic table is organized into columns and rows. The number of protons in the nucleus increases when reading the periodic table from right to left. Each row represents an energy level. The...

According to Solar Energy International, the U.S. uses 25 percent to 30 percent of the world's energy. "Fossil fuels--coal, oil and natural gas--currently provide more than 85 percent of all the...

When wrapped tightly around an egg or other fragile item in a container, cotton balls can help keep the egg from breaking as easily when dropped or shaken. This is because the cotton balls act as...

Nearly every event in life and in the environment is predicated by a chemical reaction. From the inner workings of human cells to the caramelization of an onion in a skillet to the manufacture of...

Chemical reactions change molecules into other molecules. They don't change atomic nuclei, thus, they can't change elements into different elements. Instead, they affect the electrons in the...

Organisms that can carry out photosynthesis are called autotrophs. Organisms that cannot independently produced their own food energy--- like animals in general, including humans---are called...

The Newtonian physics of the 1800's described matter and energy as two different elements. This remained the prevailing view until Albert Einstein's formula for energy and mass opened up a new...

Fossil fuels are used around the world as a way to generate energy. The U.S. Department of Energy expects the use of fossil fuels to increase during the next 20 years because increasing power...

Electric energy is one of the most used power sources on earth. Electricity itself is actually harmless to the planet and enables the human race to live with vast amounts of equipment and gadgets...

Like coal and gas power plants, nuclear power plants turn the thermal energy from fuel into electricity by heating water into steam. The high temperatures and influx of steam particles into the...

"Molecule movement" exists as a variety of components. The translational movement of molecules as complete units in three-dimensional space is one major component. Other components include...