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An object is placed at a distance of 12 cm in front of a concave mirror of radius of curvature 30 cm. List four characteristics of the image formed by the mirror. - Science

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Question

An object is placed at a distance of 12 cm in front of a concave mirror of radius of curvature 30 cm. List four characteristics of the image formed by the mirror.

Solution

Here, radius of curvature (R) of concave mirror is given 30 cm.
Therefore, focal length of the mirror,  
`f =R/2= 30/2 = 15` cm
Also, it is given that object is placed at a distance of 12 cm in front of a concave mirror . Hence, it is apparent that object is placed between the focus and pole of the mirror. 
Therefore, four properties of the image formed by the given concave mirror of the object placed between focus and pole of the mirror are:  
(i)   Image is always erect 
(ii)  Big in size 
(iii) Virtual 
(iv) Always forms behind the mirror. 

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2016-2017 (March) Delhi Set 3

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