# according to the sign convention the distance of image

An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. (iii) Mark two foci F and F' on two sides of the lens, each at a distance of 2 cm from the lens. should be placed at a distance of 54 cm on the object side of the mirror to obtain a sharp image. (3) The distances measured in the direction opposite to the direction of incident light are taken as negative. (ix) The AB is position of object. (ii) Centre line is shown by DE. According to the new Cartesian sign convention for the refraction of light through the concave and convex lens. This sign convention is known as New Cartesian Sign Convention. We draw the ray diagram as follows:(i) Draw the principal axis (a horizontal line). We are given a convex mirror. (5) Heights measured perpendicular to the principal axis, in the downward direction are taken as negative. 2020 Zigya Technology Labs Pvt. Measure distance BC. The image is real, inverted and enlarged in size. All distances parallel to the principal axis are measured from the pole of the mirror. When we deal with the reflection of light in spherical mirrors, we use a set of sign conventions called the New Cartesian Sign Convention. Find the position of the image, its nature and size. Ans. (vi) Draw a line A'B', perpendicular to principal axis from B'. The heights measured upwards and perpendiculars to the principal axis of the mirror are taken as positive. 232, Block C-3, Janakpuri, New Delhi, An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. When a point object is placed before a spherical mirror, a point images formed. All rights reserved. How far is the object placed from the lens? The following sign conventions are used by Cartesian: (1) All distances are measured from the pole of the mirror (in the case of the lens from the optic center). (v) Draw a line AD, parallel to principal axis. Here, Object size, h = + 7.0 cmObject distance, u = - 27 cmFocal length, f = - 18 cm Image distance, v = ? (6) The size of the object is always taken as positive, but the image size is positive for erect image and negative for an inverted image. According to the new Cartesian sign convention for the refraction of light through the concave and convex lens. In the case of a spherical mirror, all signs are taken from Pole of the spherical mirror, which is often called origin or origin point. https://www.zigya.com/share/U0NFTjEwMDUyOTk3. Ltd. Download books and chapters from book store. Sign is taken as + (positive) behind the spherical mirror. This sign convention is known as the Cartesian sign convention. (x) Then, measure CB' and A'B'. According to Cartesian sign convention, the focal length of a lens is given by. (iv) Draw an arrow AB of height 1 cm on the left side of lens at a distance of 5 cm from the lens. (xi) Thus the final position, nature and size of the image A'B' are:         (a) Position of image A'B' = 3.3 cm × 5 = 16.5 cm from the lens on opposite side. The height of is taken as + (positive) above the principal axis and taken as – (negative) below the principal axis. According to Cartesian sign convention, the focal length of a lens is given by. This sign convention is known as the Cartesian sign convention. Describe Expression for Bandwidth with Equation, Experiment: Refraction of a Plane Wavefront at a Plane Surface, The viral article claims CERN is about to communicate with a parallel universe, The Black Hole Breakthrough wins 2020 Nobel Physics Prize, The 12-year-old became the youngest person to achieve nuclear fusion, The “Supercooled” water is really two liquids in one, Scientists have got the maximum speed of the Sound. 3 ) the distances measured in the downward direction are taken as negative downward direction are taken as negative sign. 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