Q5 of 13 Page 127

Solve the following examples

A convex mirror has a focal length of 18 cm. The image of an object kept in front of the mirror is half the height of the object. What is the distance of the object from the mirror?

According to the question;

Focal length (f) = + 18cm;


Height of Image = Hi ;


Height of object = Ho ;


Given That;



= Magnification;


We Know that


Magnification = = (Since object is always kept to left side of mirror hence u is negative)



Hence


By Mirror Formula;



Since





.


Hence distance of the object from mirror is 18 cm.


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