(b) If the concave part is filled with water of refractive index 4/3, find the distance through which the pin should be moved, so that the image of the pin again coincides with the pin.
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Given constants:
3. Stick a pin there
The convex surface of a thin concavo-convex lens of glass of refractive index 1.5 has a radius of curvature 20cm. The concave surface has a radius of curvature 60cm. The convex side is silvered and placed on a horizontal surface.
Context question:
(a) Where should a pin be placed on the optical axis such that its image is formed at the same place?
Context answer:
15