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9. Why is it dangerous to occupy a room in which
charcoal is burning in a stove without a chimney?
10. A gas jar standing over mercury contains a
gaseous mixture. A little nitric oxide is passed up into the jar, and its contents are seen to become reddish in colour. A little caustic soda solution is next passed up, and the red colour disappears. Name one of the ingredients of the original gaseous mixture, and explain the changes that occur.
The Board of Examiners.
Candidates are requested to answer the questions on
Dynamics, and on one but not more than one of the three subjects—Heat, Sound and Light, Electricity and Magnetism.
DYNAMICS. 1. State the second law of motion, and explain why
a boy takes a preliminary run when he wishes
to jump as far as possible. 2. With what acceleration must a platform be de
scending so that the pressure of a body resting
on it may be only a quarter of its weight? 3. A bullet weighing 600 grammes, and moving at
the rate of 150 metres per second, penetrates into and lodges in a block of wood" which is
suspended by a string. The weight of the block is 30 kilogrammes. With what velocity will it begin to move?
4. At a distance 5 the attraction between two particles
is 180. What is the attraction at distance 15 ?
5. The weight of a solid in vacuo is 174 grammes.
If its specific gravity be 7.25, what will it weigh in water ?
6. Define conservation of energy. Shew that the
principle of the conservation of energy holds in the hydraulic press.
HEAT. 1. State Boyle's and Charles's laws. 2. A cubic foot of dry air at the temperature 0° C.
is heated up to 100° C., and at the same time the pressure is halved. Taking the coefficient of expansion of air as 0:003665, determine the new volume.
3. A flask of water and a closed room are of the same
temperature. The water is sprinkled over the floor. Does the temperature of the room rise or fall? Why?
4. Will water boil as quickly in a bright new kettle
as in a blackened old one ? Which will retain the heat the longer after they are removed from
the fire ? Why? 5. After mixing 50 grammes of copper at 80° C. with
57 grammes of water at 15°, it is found that. the temperature of the mixture is 20°. Taking the specific heat of water as the unit, determine
the specific heat of copper. 6. A leaden bullet weighing 2 ounces falls 100 feet.
By what amount will its temperature be raised when it reaches the ground, taking 0:3 as the specific heat of lead, and assuming that all the heat is expended in raising the temperature of the bullet ? J=772.
SOUND AND LIGHT. 1. What is meant by a wave of sound, and by the
length of a wave? 'How is sound transmitted through air?
2. What effect has wind upon a sound wave? A
spectator, from whom the wind is blowing towards a church, finds that he can hear the church bell at the top of a hill, but not at the
bottom. Explain why. 3. How many times faster should sound travel in
oxygen than in carbonic acid, their densities
being 1.106 and 1.529 respectively ? 4. A thick plate of glass is interpased obliquely
between a candle and the eye of an observer. Will the apparent position of the candle be
altered ? Draw a sketch illustrating your answer. 5. If a red coat be hanging up in a room into which
light enters through blue glass, what is its apparent colour? Account for the transparency of paper which has been soaked in oil.
6. Give a brief description of a method of finding
the velocity of light.
ELECTRICITY AND MAGNETISM. 1. Describe an experiment shewing that there are two
kinds of electricity. 2. What is meant by a unit of electricity ? How do
electrical attractions and repulsions vary (1)
with distance, (2) with quantity ? 3. Two quantities of electricity + 5 and + 8 at a
distance 9 repel each other with a force 16. With what force will quantities + 3 and + 9 repel each other at a distance 6 ?
4. Prove that the heating effect produced by the dis
charge of a Leyden jar is directly proportional to the square of the quantity of electricity, and
inversely proportional to the surface of the jar. 5. Describe Volta's arrangement known as the “crown
of cups,” and trace the electric current through the circuit.
6. What is an electro-magnet ? Describe the method
of making one.
The Board of Examiners. [Not more than six questions are to be answered.] 1. Describe as fully as you can the phenomena which occur in the heart during the different periods of its rhythmical action.
2. Describe the chemical composition of the blood,
including its gases.
3. Describe the mechanism of inspiration and of
4. Describe the structure of the kidneys, and draw
rough diagrams to illustrate your answer.
5. Describe the general characters, chemical composi
tion and functions of bile.
6. Describe the structures which enter into the for
mation of a perfect joint, and specify their several functions.
7. Describe the organ of the sense of smell.
8. Describe the structure and functions of the skin.
Draw rough diagrams to illustrate your answer.
The Board of Examiners.
[Not more than six questions are to be answered.] 1. Describe the different parts which compose a seed,
and give some account of the process of fertilization.