An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed so that a sharp focused image can be obtained?

Given: size of object, o = +7 cm distance of object, u = -27 cm focal length of concave mirror, f = -18 cm let us take size of image = I So, mirror formula is 1/v + 1/u = 1/f So, putting values of u and f, 1/v = 1/(-18) - 1/(-27) 1/v = 1/(-54) v = -54 cm So, the image is formed on the object side. magnification, m = -v/u = I/o m = -(-54)/(-27) = I/7 I = -14 cm So, the image is double in size to that of the object. Nature: real, inverted and magnified image.