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  2. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    Prentice's rule, named so after the optician Charles F. Prentice, is a formula used to determine the amount of induced prism in a lens: = where: P is the amount of prism correction (in prism dioptres) c is decentration (the distance between the pupil centre and the lens's optical centre, in millimetres)

  3. Free-air gravity anomaly - Wikipedia

    en.wikipedia.org/wiki/Free-air_gravity_anomaly

    Calculation. The free-air gravity anomaly is given by the equation: = (+) Here, is observed gravity, is the free-air correction, and is theoretical gravity.

  4. Anisometropia - Wikipedia

    en.wikipedia.org/wiki/Anisometropia

    Amblyopia. Anisometropia is a condition in which a person's eyes have substantially differing refractive power. [1] Generally, a difference in power of one diopter (1D) is the threshold for diagnosis of the condition . [2] [3] Patients may have up to 3D of anisometropia before the condition becomes clinically significant due to headache, eye ...

  5. Dioptre - Wikipedia

    en.wikipedia.org/wiki/Dioptre

    A dioptre ( British spelling) or diopter ( American spelling ), symbol dpt, is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dpt = 1 m−1. It is normally used to express the optical power of a lens or curved mirror, which is a physical quantity equal to the reciprocal of the focal length ...

  6. Eötvös effect - Wikipedia

    en.wikipedia.org/wiki/Eötvös_effect

    The force of gravity and the normal force. The resultant force acts as the required centripetal force. The mathematical derivation for the Eötvös effect for motion along the Equator explains the factor 2 in the first term of the Eötvös correction formula. What remains to be explained is the cosine factor.

  7. Equations for a falling body - Wikipedia

    en.wikipedia.org/wiki/Equations_for_a_falling_body

    We find from the formula for radial elliptic trajectories: The time t taken for an object to fall from a height r to a height x , measured from the centers of the two bodies, is given by: t = π 2 − arcsin ⁡ ( x r ) + x r ( 1 − x r ) 2 μ r 3 / 2 {\displaystyle t={\frac {{\frac {\pi }{2}}-\arcsin {\Big (}{\sqrt {\frac {x}{r}}}{\Big ...

  8. Brewster's angle - Wikipedia

    en.wikipedia.org/wiki/Brewster's_angle

    one can calculate the incident angle θ 1 = θ B at which no light is reflected: n 1 sin ⁡ θ B = n 2 sin ⁡ ( 90 ∘ − θ B ) = n 2 cos ⁡ θ B . {\displaystyle n_{1}\sin \theta _{\mathrm {B} }=n_{2}\sin(90^{\circ }-\theta _{\mathrm {B} })=n_{2}\cos \theta _{\mathrm {B} }.}

  9. Spherical aberration - Wikipedia

    en.wikipedia.org/wiki/Spherical_aberration

    Spherical aberration of collimated light incident on a concave spherical mirror. In optics, spherical aberration ( SA) is a type of aberration found in optical systems that have elements with spherical surfaces. This phenomenon commonly affects lenses and curved mirrors, as these components are often shaped in a spherical manner for ease of ...

  10. Thomas precession - Wikipedia

    en.wikipedia.org/wiki/Thomas_precession

    Thomas precession gives a correction to the precession of a Foucault pendulum. For a Foucault pendulum located in the city of Nijmegen in the Netherlands the correction is: ω ≈ 9.5 ⋅ 10 − 7 a r c s e c o n d s / d a y . {\displaystyle \omega \approx 9.5\cdot 10^{-7}\,\mathrm {arcseconds} /\mathrm {day} .}

  11. Spherical coordinate system - Wikipedia

    en.wikipedia.org/wiki/Spherical_coordinate_system

    The spherical coordinates of a point in the ISO convention (i.e. for physics: radius r, inclination θ, azimuth φ) can be obtained from its Cartesian coordinates (x, y, z) by the formulae. The inverse tangent denoted in φ = arctan y x must be suitably defined, taking into account the correct quadrant of (x, y).