Calendar: 1869-1870 Page 516

518 Bcpartiuent of tije pplirt Sciences II -Uibimtg anU iHatfjemattrt TAe Papers are ihe same in each case as those given for the Department of General Literature and Science ΠΙ -jlatural $PojiopI SECOND AND THIRD YEARS Cjrptrimental ttSki Account for the formation of the image of an object placed in front of plane mirror and prove the law of reflection on the principles of the Undulatory theory luminous point being placed between two plane mirrors inclined to one another at an angle of 45 find the number of images and show that they all lje in circle Describe the common astronomical telescope and draw figure tracing the course through it of pencils of light coming from distant object What is the relation between the positions of the geo- metrical foci for lens and how would you practically determine the focal length of lens Give Foucault's method of comparing the brightness of two sources of light and describe the apparatus employed Show how to find the index of refraction of transparent solid or liquid prism Describe the solar spectrum and its heating illuminating and actinic properties In what way does it differ from the spectra of incandescent solids or liquids Account for this difference What effect is produced on ray of light in passing through -crystal of Iceland spar in plane passing through the axis of the crystal If the light after passing through the crystal be examined by means of Nicol's prism what properties it it found to possess Explain clearly what is meant by Interference How may