. The Ontario high school physics. 338 LENSES. Fig. 398. -How to draw the image in a con-cave lens. througli the lens, but on producing them backwards they inter-sect at Q. QP is the imageof QP. It is virtual, erectand larger than the object. For a concave lens we havethe construction shown in The image is virtual, erect and smaller than the object. 389. Magnification. On examining Figs. 396-8, it will beseen that the triangles QAP, QAP are similar, and as before(I 862) calling the ratio of the length of the image to that ofthe object tlie magnification, we have -fi f _ ^ Q ■^^ _ <
. The Ontario high school physics. 338 LENSES. Fig. 398. -How to draw the image in a con-cave lens. througli the lens, but on producing them backwards they inter-sect at Q. QP is the imageof QP. It is virtual, erectand larger than the object. For a concave lens we havethe construction shown in The image is virtual, erect and smaller than the object. 389. Magnification. On examining Figs. 396-8, it will beseen that the triangles QAP, QAP are similar, and as before(I 862) calling the ratio of the length of the image to that ofthe object tlie magnification, we have -fi f _ ^ Q ■^^ _ <listance of image from lens° FQ AF distance of object from lens 390. Vision Through a Lens. In § 388 is explained amethod of finding the position of an image produced by a lensbut it should be remembered that this is simply a geometricalconstruction and that the rays shoAvn there are usually notthose by which the eye sees the image. Let us draw the rayswhich actually enter the eye. In Fig. 399 PQ is the (real) image of PQ, and E is the ey
Size: 2415px × 1035px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublishe, booksubjectphysics
