Magnification by a lens of an object at distance 10 cm from it is -2. Now a second lens is placed exactly at the same position where first was kept, without changing the distance between object and lens. The magnification by this second lens is -3. (a) Now both the lenses are kept in contact at the same place. What will be the new magnification. (b) What is the focal length of the combination when both lenses are in contact?

Magnification by a lens of an object at distance 10 cm from it is -2.

1.	Magnification by a lens of an object at distance 10 cm from it is -2. Now a second lens is placed exactly at the same position where first was kept, without changing the distance between object and lens. The magnification by this second lens is -3. (a) Now both the lenses are kept in contact at the same place. What will be the new magnification. (b) What is the focal length of the combination when both lenses are in contact?
Answer» Solution :`(a) (-6)/(11) , (b ) (60)/(17) cm`

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