Light from the Land of the SphinxE. Stock, 1896 - 320 頁 |
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第 1 到 5 筆結果,共 41 筆
第 5 頁
... portion of S , or this region is such that S is only partly visible from any point of it . This third region is called a penumbra . It is clear that the illumination in it will increase uniformly as we pass outward from the boundary A B ...
... portion of S , or this region is such that S is only partly visible from any point of it . This third region is called a penumbra . It is clear that the illumination in it will increase uniformly as we pass outward from the boundary A B ...
第 7 頁
... portion in the shadow of the rod formed by one source is then illuminated only by the other source , and we have two adjoining portions of the screen illuminated , one by one source , and the other by the other . Now let five candles of ...
... portion in the shadow of the rod formed by one source is then illuminated only by the other source , and we have two adjoining portions of the screen illuminated , one by one source , and the other by the other . Now let five candles of ...
第 8 頁
... portions of the surface subtending equal solid angles , or having the same apparent size at the eye , send equal amounts ... portion of area s ' cos i . And it follows that the illumination emitted in any direction by a given element of ...
... portions of the surface subtending equal solid angles , or having the same apparent size at the eye , send equal amounts ... portion of area s ' cos i . And it follows that the illumination emitted in any direction by a given element of ...
第 9 頁
... portion of its area subtends at the centre is measured by the number of units of area in that portion . This is also called the solid angle of the cone which has its vertex at the centre and whose sides pass through the contour of the ...
... portion of its area subtends at the centre is measured by the number of units of area in that portion . This is also called the solid angle of the cone which has its vertex at the centre and whose sides pass through the contour of the ...
第 11 頁
... portions of surface examined should be illuminated normally . Now , the surface in the shadow formed by each light is ... portion , in the centre , is made more translucent than the rest by means of a spot of grease . The lights are ...
... portions of surface examined should be illuminated normally . Now , the surface in the shadow formed by each light is ... portion , in the centre , is made more translucent than the rest by means of a spot of grease . The lights are ...
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常見字詞
aberration achromatic analyzer angles of incidence aperture apparatus astigmatic axis bright band called centre circle concave lens consider convex lens corresponding cos² crystal denote direction displacement distance disturbance edge ellipse emergent equal eye-piece film focal length focal lines given glass illumination image formed incident light index of refraction lenses light falls magnifying medium minimum deviation Nicol normal object and image object-glass optical ordinary parallel particle pass path pencil pencil of light perpendicular phase phase-difference placed plane of polarization plane polarized light plate polarized beam principal focus principal plane prism produced quantity radius ratio reflected rays reflexion refractive index refrangibility retina rhomb right angles rotated screen seen side sin² slit small object solid angle spectrum spherical spherical aberration straight line substance Suppose surface telescope thickness velocity vibrations violet virtual wave wave-front wave-length wave-surface white light
熱門章節
第 42 頁 - ... that the ratio of the sines of the angles of incidence and refraction is constant for refraction in the same medium, was effected by Snell and Descartes.
第 75 頁 - ... traversing the lens are reflected from a concave mirror and again refracted by the lens, forming a real inverted image coincident with the object : if the distance between the lens and the mirror is a shew that the radius of the mirror is a + J /. 21. A small air-bubble in a sphere of glass 4 inches in diameter appears when looked at so that the bubble and the centre of the sphere are in a line with the eye, to be 1 inch from the surface. What is its true distance ? (jt=l-5.) 23.
第 160 頁 - ... they should have been previously cut in the house, from the pattern given by one of the cards that had been mounted and cut in the instrument. In mounting the instrument in place, the points to attend to are, (1) that it shall be level as regards east and west, (2) that the axis of the ring shall be inclined to the horizon at an angle equal to the latitude of the place...
第 75 頁 - Taking the refractive index from air to glass as \, draw an accurate picture of the path of a ray of monochromatic light, which falls at an incidence of 60° on the face of a prism, whose vertical angle is 30°.
第 311 頁 - ... film was still wet, and the black has floated toward the surface. Paint behavior is not ordinarily erratic; under similar painting conditions, similar results may be expected; and the painter who has learned the characteristics of each of his pigments is able to control their effects. Additive Colors. When white light passes through a prism it is broken up into its component parts and the rays emerge in the familiar rainbow or spectrum arrangement, the rays at the red end having the longest wave...
第 43 頁 - The figure shows the passage of the ray for this case, i and r are the angles of incidence and refraction at the first surface, at the point A.