See the figure Find the equivalent focal length of the combination shown in the figure and position of image.
The ratio of powers of a thin convex and thin concave lens is 3/2 and equivalent focal length of their combination is 30 cm. Then their focal lengths respectively are
A convex lens of focal length 'f' is placed in contact with a concave lens of the same focal length. The equivalent focal length of the combination is
(a) Using the ray diagram for a system of two lenses of focal lengths f_(1) and f_(2) in contact with each other, show that the two lens system can be regarded as equivalent to a single lens of focal length f, where (1)/(f)=(1)/(f_(1))+(1)/(f_(2)) Also write the relation for the equivalent power of the lens combination. (b) Determine the position of the image formed by the lens combination given in the figure.
A 20cm convex lens is placed in contact with a diverting lens of unknown focal length ,The lens combination acts as a converging lens and has a length of 30cm .What is the focal length of the diverging lens.
Find the focal length of the lens shown in Fig.
A thin convex lens of focal length 10 cm is placed in contact with a concave lens of same material and of same focal length. The focal length of combination will be
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