English

English Essay

Energy

The energy term has different meanings and definitions related to the idea of a capacity to act process or put in motion. In physics, "energy" is defined as the ability to do work. In technology and economy, "energy" refers to a natural resource (including associated technology) to extract, transform and give economic or industrial use.

Energy in various types of physical systems

Energy is a physical quantity that takes various forms, is involved in all processes of change in physical state, is transformed and transmitted depends on the fixed reference system and is retained. Therefore, everybody is able to possess power based on their movement, position, temperature, mass, chemical composition and other properties. In the various disciplines of physics and science, there are several definitions of energy, all consistent and complementary, and they all always related to the concept of work.

Environmental impact of energy

Human societies generate a significant impact on the environment as a result of their activities. Agriculture, livestock and fisheries, mining, industry or services are responsible for what often leads to a serious deterioration.

In this regard it is noted that the production and consumption of energy generated effects that manifest as global warming, air pollution, acid rain, radioactive contamination or oil spills, among others, resulting in severe environmental conditions. To assess the impact of energy-related activities must take into account its full cycle, not just its final stages. Thus, one should not focus only on the purely immediate processes of production and consumption, but should also consider that certain mining activities require energy sources, the impact of transport prior to use and treatment processes to be carried out before being used. Also be studied not only the emission sources of pollutants to the atmosphere, hydrosphere and soils but have to follow them to their final destination in ecosystems, eventually to man. All this considering that their effects are likely to spread in time and space.

Water

The water (from the Latin aqua) is a substance whose molecule consists of two atoms of hydrogen and one oxygen (H 2 O). Is essential for survival of all known forms of life. The term water generally refers to the substance in its state liquid, but it can be in form solid called ice, and in a gas called steam. Water covers 71% of the surface of the earth's crust and it is localized mainly in the oceans which accounts for 96.5% of total water, the glaciers and ice caps have 1.74%, the underground reservoirs (aquifers), the permafrost and continental glaciers account for 1.72% and the remaining 0.04% is distributed in descending order from lakes, soil moisture, air, reservoirs, rivers and living things. Water is a common element of the solar system, a fact confirmed by recent discoveries. Can be found mainly in the form of ice, in fact, is the base material of comets and their tails up steam.

Types of water

Water can be present in three states to be one of the few substances that can ...