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  2. Earth's internal heat budget - Wikipedia

    en.wikipedia.org/wiki/Earth's_internal_heat_budget

    Earth's tectonic evolution over time from a molten state at 4.5 Ga, [11] to a single-plate lithosphere, [24] to modern plate tectonics sometime between 3.2 Ga [25] and 1.0 Ga [26] Primordial heat energy comes from the potential energy released by collapsing a large amount of matter into a gravity well, and the kinetic energy of accreted matter.

  3. Ecological pyramid - Wikipedia

    en.wikipedia.org/wiki/Ecological_pyramid

    When energy is transferred to higher trophic levels, on average only about 10% is used at each level to build biomass, becoming stored energy. The rest goes to metabolic processes such as growth, respiration, and reproduction. [2] Advantages of the pyramid of energy as a representation: It takes account of the rate of production over a period ...

  4. Heat transfer - Wikipedia

    en.wikipedia.org/wiki/Heat_transfer

    Radiative heat transfer is the transfer of energy via thermal radiation, i.e., electromagnetic waves. [1] It occurs across vacuum or any transparent medium ( solid or fluid or gas ). [ 15 ] Thermal radiation is emitted by all objects at temperatures above absolute zero , due to random movements of atoms and molecules in matter.

  5. Transfer of energy - Wikipedia

    en.wikipedia.org/wiki/Transfer_of_energy

    Transfer of energy may refer to: Energy transformation, also known as energy conversion, is the process of changing energy from one form to another. Heat transfer, the exchange of thermal energy via conduction, convection and radiation; Collision, an event in which two or more bodies exert forces on each other over a relatively short time

  6. International General Certificate of Secondary Education

    en.wikipedia.org/wiki/International_General...

    The change from an A*-G grading system to a 9-1 grading system by English GCSE qualifications has led to a 9-1 grade International General Certificate of Secondary Education being made available. [13] Before, this qualification was graded on an 8-point scale from A* to G with a 9th grade “U” signifying “Ungraded”.

  7. Energy transformation - Wikipedia

    en.wikipedia.org/wiki/Energy_transformation

    Fire is an example of energy transformation Energy transformation using Energy Systems Language. Energy transformation, also known as energy conversion, is the process of changing energy from one form to another. [1] In physics, energy is a quantity that provides the capacity to perform work or moving (e.g. lifting an object) or provides heat.

  8. Triplet-triplet annihilation - Wikipedia

    en.wikipedia.org/wiki/Triplet-Triplet_Annihilation

    A Jablonski diagram describing the mechanism of triplet-triplet annihilation. The energy of the first triplet excited state (T 1) is transferred to a second triplet excited state (T 1), resulting in (1) the first T 1 returning to the singlet ground state S0 and (2) the second T 1 promoting to the singlet excited state (S 1).

  9. Stefan–Boltzmann law - Wikipedia

    en.wikipedia.org/wiki/Stefan–Boltzmann_law

    Stefan surmised that 1/3 of the energy flux from the Sun is absorbed by the Earth's atmosphere, so he took for the correct Sun's energy flux a value 3/2 times greater than Soret's value, namely 29 × 3/2 = 43.5. Precise measurements of atmospheric absorption were not made until 1888 and 1904. The temperature Stefan obtained was a median value ...