enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Punch (tool) - Wikipedia

    en.wikipedia.org/wiki/Punch_(tool)

    A prick punch is similar to a center punch but used for marking out. It has a sharper angled tip to produce a narrower and deeper indentation. The indentation can then be enlarged with a center punch for drilling. The tip of a prick punch is 60 degrees (the angle depends on what type of prick punch one is using). [1] It is also known as a dot ...

  3. Tetrahedral molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Tetrahedral_molecular_geometry

    This angle may be calculated from the dot product of the two vectors, defined as a ⋅ b = ‖ a ‖ ‖ b ‖ cos θ where ‖ a ‖ denotes the length of vector a. As shown in the diagram, the dot product here is –1 and the length of each vector is √ 3, so that cos θ = – ⁠ 1 / 3 ⁠ and the tetrahedral bond angle θ = arccos ...

  4. Automatic center punch - Wikipedia

    en.wikipedia.org/wiki/Automatic_center_punch

    The punch; The intermediate rod (tumbler) The hammer (hammer mass) The hammer mass is spring-loaded from the back of the punch by a large spring. (The spring's preload compression can usually be adjusted by loosening or tightening the end cap at the back-most portion of the punch, to decrease or increase the force of the punch.)

  5. Spherical coordinate system - Wikipedia

    en.wikipedia.org/wiki/Spherical_coordinate_system

    The physics convention. Spherical coordinates (r, θ, φ) as commonly used: (ISO 80000-2:2019): radial distance r (slant distance to origin), polar angle θ (angle with respect to positive polar axis), and azimuthal angle φ (angle of rotation from the initial meridian plane). This is the convention followed in this article.

  6. List of dimensionless quantities - Wikipedia

    en.wikipedia.org/wiki/List_of_dimensionless...

    chemistry (Proportion of "active" molecules or atoms) Arrhenius number = Svante Arrhenius: chemistry (ratio of activation energy to thermal energy) [1] Atomic weight: M: chemistry (mass of one atom divided by the atomic mass constant, 1 Da) Bodenstein number: Bo or Bd

  7. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Lewis structure of a water molecule. Lewis structures – also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) – are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule.

  8. List of equations in classical mechanics - Wikipedia

    en.wikipedia.org/wiki/List_of_equations_in...

    Classical mechanics is the branch of physics used to describe the motion of macroscopic objects. [1] It is the most familiar of the theories of physics. The concepts it covers, such as mass, acceleration, and force, are commonly used and known. [2] The subject is based upon a three-dimensional Euclidean space with fixed axes, called a frame of ...

  9. Physical chemistry - Wikipedia

    en.wikipedia.org/wiki/Physical_chemistry

    Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mechanics, analytical dynamics and chemical equilibria.