enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Delta potential - Wikipedia

    en.wikipedia.org/wiki/Delta_potential

    The delta potential is the potential = (), where δ(x) is the Dirac delta function. It is called a delta potential well if λ is negative, and a delta potential barrier if λ is positive. The delta has been defined to occur at the origin for simplicity; a shift in the delta function's argument does not change any of the following results.

  3. Nabla symbol - Wikipedia

    en.wikipedia.org/wiki/Nabla_symbol

    The nabla is a triangular symbol resembling an inverted Greek delta: [1] or ∇. The name comes, by reason of the symbol's shape, from the Hellenistic Greek word νάβλα for a Phoenician harp, [2] [3] and was suggested by the encyclopedist William Robertson Smith in an 1870 letter to Peter Guthrie Tait.

  4. ΔT - Wikipedia

    en.wikipedia.org/wiki/ΔT

    View history; Tools. Tools. move to sidebar hide. Actions Read; Edit; View history; ... The symbols Δt and ΔT (spoken as "delta T") are commonly used in a variety ...

  5. Delta ray - Wikipedia

    en.wikipedia.org/wiki/Delta_ray

    A delta ray is a secondary electron with enough energy to escape a significant distance away from the primary radiation beam and produce further ionization. [1]: 25 The term is sometimes used to describe any recoil particle caused by secondary ionization. The term was coined by J. J. Thomson.

  6. Glossary of physics - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_physics

    A branch of physics that studies atoms as isolated systems of electrons and an atomic nucleus. Compare nuclear physics. atomic structure atomic weight (A) The sum total of protons (or electrons) and neutrons within an atom. audio frequency A periodic vibration whose frequency is in the band audible to the average human, the human hearing range.

  7. Gibbs free energy - Wikipedia

    en.wikipedia.org/wiki/Gibbs_free_energy

    In the infinitesimal expression, the term involving the chemical potential accounts for changes in Gibbs free energy resulting from an influx or outflux of particles. In other words, it holds for an open system or for a closed, chemically reacting system where the N i are changing. For a closed, non-reacting system, this term may be dropped.

  8. ΔT (timekeeping) - Wikipedia

    en.wikipedia.org/wiki/ΔT_(timekeeping)

    TT-UT1 2000+ ΔT vs. time from 1657 to 2022 [1] [2] In precise timekeeping, ΔT (Delta T, delta-T, deltaT, or DT) is a measure of the cumulative effect of the departure of the Earth's rotation period from the fixed-length day of International Atomic Time (86,400 seconds).

  9. Delta-v - Wikipedia

    en.wikipedia.org/wiki/Delta-v

    Delta-v is typically provided by the thrust of a rocket engine, but can be created by other engines. The time-rate of change of delta-v is the magnitude of the acceleration caused by the engines, i.e., the thrust per total vehicle mass. The actual acceleration vector would be found by adding thrust per mass on to the gravity vector and the ...