A spherical mirror produces an image of magnification -1 on a screen placed at a distance of 50 cm from the mirror. (a) Write the type of mirror. (b) Find the distance of the image from the object. (c) What is the focal length of the mirror?

(a) As magnification is negative (-1), the image will be below the principal axis compared to the object and will be formed by a Concave Mirror.
(b) The distance of the image from the object is zero. A real and inverted image of the same size is formed at the same place where the object is placed.
(c) For a spherical mirror, the relationship between the focal length (F) and the radius of curvature (R) is given by: F = R/2. Since the image is formed at a distance of 50 cm from the mirror (which is equal to both image distance, v, and object distance, u, in this case), then the radius of curvature R = 50 cm. Therefore, the focal length is: F = 50 cm / 2 = 25 cm