Calendar: 1880-1881 Page 667

APPLIED SCIENCES 667 person is equidistant from two plane mirrors which meet in the corner of square room Explain in what way the image of himself which he sees when looking towards the corner of the room differs from the images which he sees when looking towards the sides of the room Show how the hypothenuse face of right-angled prism may be used as reflector Explain the connection between the refractive index of medium and the angle at which an emergent ray is totally reflected What evidence has the spectrum of stars given as to the relative motion between them and the solar system Describe the principal methods of obtaining beam of plane-polarized light and state the special advantages of each method Account for the delicate shades of colour sometimes seen on an oyster shell Explain the appearance presented when beam of light falls upon plate on which very fine equidistant lines have been ruled very close together 10 Give the form of the wave-surface for Iceland spar What effect is produced on ray of light in passing through crystal of Iceland spar Explain the effects which are produced when the light is examined by passing it through Nicol's prism How are the results modified by introducing plate of selenite between the Iceland spar and the Nicol's prism FIRST YEAR globe the radius of which is cms rests at the bottom of cubical vessel 60 cms in height full of water Find the total pressure on the globe Find also the diminution of pressure on the sides and base of the vessel caused by the removal of the globe from the water Area of surface of globe 47rr2 vol πτ3 piece of iron sp gr 21 and weighing 721 grammes is tied to piece of wood weighing 600 grammes and the weight of both in water is 221 grammes Find the sp gr of the wood