Work and heat energy

The energy mainly comes under two forms: work-energy and heat-energy. The former can be fully transformed into the latter, but not vice-versa because the heat tends to disperse.
The energy that produces work can again be divided into potential and kinetic energy. Potential energy is connected to the respective positions of two bodies, for example the gravity pull increases insofar as the distance between a body and the centre of the Earth increases. Kinetic energy is the energy of the chaotic movement of molecules.
By throwing a ball up into the air, its kinetic energy increases. While moving upwards, the ball looses kinetic energy and increases its potential energy. When the topmost point is reached, the potential energy reaches its peak and the kinetic energy is nil, and the ball starts falling down. During its downfall, the ball increases its kinetic energy while the potential energy decreases. By bouncing on the ground, the ball transfers part of its kinetic energy to the Earth as heat.

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Facts

  • Where does energy come from?

    Every day the Earth receives enough solar energy to satisfy the global energy need...

    Electricity and electrons

    In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...

    Peat and peat-bogs

    The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…

  • Geographical distribution of energy

    Every day the Earth receives enough solar energy to satisfy the global energy need. Unfortunately we cannot exploit all this…

    Orimulsion

    In order to improve supply security, and therefore the diversification of sources to produce electric energy...

    Cracking operations

    At the end of the fractional distillation, long hydrocarbon molecules can be transformed into lighter molecules by means of more…

  • Hydrogen from biomass

    Hydrogen is an energy carrier that allows to generate energy in an environmentally sustainable way...

    ITER fusion reactor

    The reactor that will be able to produce electronuclear energy without risk of explosion or radioactive waste...

    Phyto-depuration

    A very interesting project has been carried out by Lombardy region...

  • 2 March 2011

    Where does energy come from?

    Every day the Earth receives enough solar energy to satisfy the global energy need...

    Electricity and electrons

    In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...

  • Peat and peat-bogs

    The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…

    Geographical distribution of energy

    Every day the Earth receives enough solar energy to satisfy the global energy need. Unfortunately we cannot exploit all this…

  • Orimulsion

    In order to improve supply security, and therefore the diversification of sources to produce electric energy...

    Cracking operations

    At the end of the fractional distillation, long hydrocarbon molecules can be transformed into lighter molecules by means of more…

  • Where does energy come from?

    Every day the Earth receives enough solar energy to satisfy the global energy need...

  • Electricity and electrons

    In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...

  • Peat and peat-bogs

    The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…