A fish is looking at a 1.0 m high plant at the edge of a pond. Will the plant appear to the fish shorter or taller than its actual height? Draw a ray diagram to support your answer.

A student puts his pencil into an empty trough and observes the pencil from the position as indicated in the figure.

(i) What change will be observed in the appearance of the pencil when water is poured into the trough?

(ii) Name the phenomenon which accounts for the above-started observation.

(iii) Complete the diagram showing how the student’s eye sees the pencil through water.

A coin is placed at the bottom of a beaker containing water (refractive index = 4/3) at a depth of 16 cm. By what height the coin appears to be raised when seen from vertically above?

A postage stamp kept below a rectangular glass slab of refractive index 1.5 when viewed from vertically above it, appears to be raised by 7.0 mm. Calculate the thickness of the glass slab.