When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. User error - Wikipedia

    en.wikipedia.org/wiki/User_error

    Phrases used by the tech savvy to mean that a problem is caused entirely by the fault of the user include PEBKAC [8] (an acronym for "problem exists between keyboard and chair"), PEBCAK [9] (an alternative, but similar, acronym for "problem exists between chair and keyboard"), POBCAK (a US government/military acronym for "problem occurs between ...

  3. Del in cylindrical and spherical coordinates - Wikipedia

    en.wikipedia.org/wiki/Del_in_cylindrical_and...

    The polar angle is denoted by [,]: it is the angle between the z-axis and the radial vector connecting the origin to the point in question. The azimuthal angle is denoted by φ ∈ [ 0 , 2 π ] {\displaystyle \varphi \in [0,2\pi ]} : it is the angle between the x -axis and the projection of the radial vector onto the xy -plane.

  4. Polar alignment - Wikipedia

    en.wikipedia.org/wiki/Polar_alignment

    In the Northern Hemisphere, rough alignment can be done by visually aligning the axis of the telescope mount with Polaris.In the Southern hemisphere or places where Polaris is not visible, a rough alignment can be performed by ensuring the mount is level, adjusting the latitude adjustment pointer to match the observer's latitude, and aligning the axis of the mount with true south or north by ...

  5. Equatorial mount - Wikipedia

    en.wikipedia.org/wiki/Equatorial_mount

    The computer monitors the telescope's position in the sky. The operator must push the telescope. Go-to systems use (in most cases) a worm and ring gear system driven by servo or stepper motors, and the operator need not touch the instrument at all to change its position in the sky.

  6. Setting circles - Wikipedia

    en.wikipedia.org/wiki/Setting_circles

    Also, even the finest graduations on setting circles are usually more than a degree apart, which makes them difficult to read accurately, especially in the dark. Nothing can be done if the optical tube is not perpendicular to the declination axis or if the R.A. and Dec axes are not perpendicular, because these problems are next to impossible to ...

  7. Polarity symbols - Wikipedia

    en.wikipedia.org/wiki/Polarity_symbols

    Diagram showing positive tip polarity on the left and negative tip polarity on the right. To read diagram: The center positive drawing on the left indicates that the center (also known as the tip) of the output plug is positive (+) and the barrel (ring) of the output plug is negative (−).

  8. Universal polar stereographic coordinate system - Wikipedia

    en.wikipedia.org/wiki/Universal_Polar...

    The universal polar stereographic (UPS) coordinate system is used in conjunction with the universal transverse Mercator (UTM) coordinate system to locate positions on the surface of the Earth. Like the UTM coordinate system, the UPS coordinate system uses a metric-based cartesian grid laid out on a conformally projected surface.

  9. Equatorial coordinate system - Wikipedia

    en.wikipedia.org/wiki/Equatorial_coordinate_system

    A right-handed convention specifies a y axis 90° to the east in the fundamental plane; the z axis is the north polar axis. The reference frame does not rotate with the Earth, rather, the Earth rotates around the z axis. There are a number of rectangular variants of equatorial coordinates. All have: The origin at the centre of the Earth.