Energy, in all its forms, belongs to the most fundamental elements in our universe.
We are using energy to live or to do work, our cities are lighted by energy, our vehicles are powered by energy, as are trains, planes, boats, and rockets. We use energy to warm our homes, to cook our food, to play our music, or to watch television. Energy is needed to power a tractor on a farm or to allow machines in a factory run.
Energy coming from the Sun provides light at daytime and it dries our clothes if we hang them outside on a line. The Sun’s energy allows plants to grow, and animals again eat the energy that is stored in these plants to give them energy. A predator animal eats his prey, which in return provides energy again for the predator. One way or another, everything that we do is related to energy.
Energy may also be defined as ‘the ability to do work’.
Our body transforms the energy that is stored in food into the energy required to do work. At whatever we do we are burning energy derived from food in our systems. Thinking, reading, or writing are also forms of ‘work’, often even hard work, and also objects, for example, light bulbs, cars, boats, planes, or machinery are transforming energy into work. Work actually is meaning moving, warming, lighting, lifting, or stopping something. These activities are all types of work that require energy, however, where does this energy come from?
There are numerous sources of energy, and here we will take a closer look at the various forms of energy that are making our world work. Energy is playing a critical role in everything we do in our daily lives. Let’s check out some forms of energy:
Keep in mind that Energy Conversion is the process of transforming one type of energy into another form. For example, with nuclear energy we change it in to heat, and with solar energy we transform it in to electrical energy.
There are three basic methods that are used for the conversion of energy:
Through the action of forces. This is a category that includes a number of special categories:
Gravity is accelerating falling objects by converting objects’ potential energy into kinetic energy. And when objects are lifted, the gravitational field is storing energy that is exerted by lifting, as potential energy in the objects’ system.
Electric and Magnetic Field Forces
Charged particles that are exerted to electrical fields are possessing potential energy near electric fields that compares to objects in gravitational fields. A gravitational field can accelerate particles and the potential energy of a particle will be converted into kinetic energy. Likewise can charged particles interact, through the electric and magnetic field they create, and transfer energy between them, or as happens when an electrical current in applied in a conductor, it may cause molecules to vibrate, meaning electrical potential energy is converted into heat.
The macroscopic, or large-scale energy of objects is transformed into heat, or thermal energy, when objects slide against other objects. This means that the kinetic and potential energy of an object in relation to its position or motion, is converted into heat, without counting the heat or thermal energy the system already has. The sliding motion is causing molecules on the objects’ surfaces to interact through electromagnetic fields and begin to vibrate.
When atoms are absorbing or emitting photons of light. When light is falling on objects, photons may pass through the objects, the objects may reflect them, or the atoms that make up the objects may absorb them. If the larger part of these photons are passing through, we say that an object is transparent. Reflections may be diffuse or coherent, depending on how rough or smooth the object’s surface is, and when photons are absorbed, their energy may be converted and split up in a number of ways:
The Photo-thermal Effect: the absorbed energy is producing thermal energy in an object, or heat. In this process, the energy of photons is causing molecules to vibrate (phonons), and this actually is heat energy.
The Photo-electric Effect: the absorbed energy is converted into kinetic energy in conduction electrons, resulting in electrical energy.
The Photo-chemical Effect: the energy causes chemical changes where it can be effectively stored.
When nuclear reactions occur, subatomic particles that form the nuclei of atoms are rearranged. There are 2 basic forms of nuclear reaction, Fission, when nuclei are split, and Fusion, where nuclei are combined. More reading about energy conversion click here.