subota, 11.06.2011.

BASIC FORMS OF ENERGY 5.th OPTIONAL THEME 5.2./1

1. What is energy?

Energy is a characteristic of the body due to which it can perform some operation.

2. How operation operates?

The operation is done at use of force F in a particular path s while is opposited by other force.

3. How can completed operation can be manifested?

While performing the operation occurs a change in state of body on which force operates (change in shape, position, momentum, energy ...)

4. Is it possible to create or destroy energy?

No, energy exist in the universe and it can only be transformed from one form to another.

5. Specify the basic forms of energy.

The basic forms of energy are mechanical, chemical, thermal, nuclear, electrical, light and biological.

6. Describe the mechanical energy.

Mechanical energy appears as potential and kinetic. Potential energy posses body when they are idle, and as an example we can cite the energy of water in accumulation lake, or compressed air energy in tank. Kinetic energy is possesd by body in the state of motion.

• The mechanical energy of water, waves and wind is generated from the conversion of solar radiation.
• Mechanical tidal energy is a result of gravitational forces of the Moon and the Sun.
• Mechanical energy of machinery is produced by electrical and chemical energy of fuel.
• Mechanical energy of muscle arises from the direct conversion of chemical energy of food into the cells of living beings with the mediation of enzymes.

7. Describe the chemical energy.

Chemical energy can be found in fuel, food and batteries.
Chemical energy of fuel and food was and is created by process of assimilation of convertion from solar radiation. Assimilation is happening in your plant leaf, and thereby joining of inorganic compounds, carbon dioxide and water into organic compound starch. The process takes place with the mediation of chlorophyll (green matter) and thereby is accumulated heat energy of Sun.
Batteries get chemical energy during the first charge by convertion from electrical energy.

8. Describe heat energy.

Heat energy is produced from converting chemical energy of fuel. Fuel combustion releases that energy of solar radiation that is accumulated process of assimilation.
Geothermal energy is also heat energy. It was formed during the Earth's formation. It can be used directly or by using geothermal water to generate electricity (geothermal). Visit the site of geothermal energy on the Internet.
The oceans have a tremendous amount of heat created from the conversion of solar radiation, but can not be rationally used.

9. Describe nuclear energy.

Nuclear energy have uranium 235, uranium 233 and plutonium 239. Uranium 235 is a natural metal, and uranium 233 and plutonium, are artificial. Uranium 233 is created by processing of thorium and plutonium we get by processing of uranium 238. Nuclear fuels are formed in ancient geological periods when heavy metals are created. Radioactive decay of nuclear fuels releases large amounts of heat that is used to generate electricity.

10. Description of the electrical energy.

Electricity we get:

• The hydro conversion from mechanical energy of water.
• The power plants converting chemical energy from fossil fuels.
• In nuclear power plants.
• The batteries, and photovoltaic modules.

11. Describe the energy of light.

Comes as part of solar radiation, moving at the speed of 300,000 km / s can be obtained from the conversion of electricity using different types of bulbs.

12. Describe biological energy.

Biological energy occurs with biological oxidation (dissimilation) of fat, protein and carbohydrates from food. It is essentially a direct conversion of chemical energy of food into heat and mechanical operation efficiency by about 20%.
Thermal energy is needed to maintain body temperature, and mechanical operation for the functioning of organs and maintenance activities. A smaller proportion of the energy conversion takes place in the digestive system, and most of it in cells along mediation of enzymes in which the key role has phosphorus.
Biological decomposition of plant and animal parts with the mediation of microorganisms also releases biological energy.

13. What is dark energy?

The latest space research showed that it consists of only 4% ordinary matter. The remaining 96% consists of mysterious dark matter components of 23% and 73% dark energy. The universe was created 13.7 billion years ago started by big bang and since then has been constantly expanding. Expanding speed is currently 71 km / sec. and constantly increasing, and it is responsible for dark energy.

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