The focal length of a thin biconvex lens is 20cm. When an object is moved from a distance of 25cm in front of it to 50cm, the magnification of its image changes from m_(25)to m_(50). The ration m_(25)//m_(50) is

The focal length of a thin biconvex lens is 20cm. When an object is mo

1.	The focal length of a thin biconvex lens is 20cm. When an object is moved from a distance of 25cm in front of it to 50cm, the magnification of its image changes from m_(25)to m_(50). The ration m_(25)//m_(50) is
Answer» SOLUTION :m=(F)/(f+u)`

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The focal length of a thin biconvex lens is 20cm. When an object is moved from a distance of 25cm in front of it to 50cm, the magnification of its image changes from m_(25)to m_(50). The ration m_(25)//m_(50) is

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