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approximately in the prime vertical, the interval between the two passages being two hours sidereal time. The altitude at eastern passage is observed to be 10' greater than at western passage. Determine the latitude of the place, and the true azimuth of the plane swept out by the line of collimation.
2. Reduce the levels given by method of rises and
falls, and by collimation method, and give all necessary checks :
3. Describe the methods adopted in mining surveys for
transferring azimuths from the surface to the underground workings.
SURVEYING, LEVELLING, MENSURATION,
1. Deduce the formula for the volume of a sphere.
2. A shell of cast iron 15 inches diameter weighs
150 lbs. What is the thickness of the shell, and what would its weight be if filled with mercury ? Specific gravity of mercury is 13.6.
3. It is required to excavate an earthen tank of 1,000
cube yards capacity, in level ground, the bottom being 20 feet square, the end slopes 4 to 1, and the side slopes 1} to 1. What will the depth be ?
1. Plot a section from the levels given below, and
grade it for main road traffic. Figure in formation levels, depths of cuttings, and heights of
banks; draw cross sections at 12 chains and 20 chains, and indicate what provision you would make for flood water.
0 10 12 15 20
100 Joins existing road.
River-bed level 60, flood level 85, 70 rapid current, drains 1,200 70
square miles mountainous
country. 80 110 105 Small creek drains į sq. mile. 110 120 Joins existing road.
30 35 40 45 50
2. Sirius is observed on 7th November, 1895, in lati
tude 37°48' south, longitude 9 hrs. 40 min. 14 sec. east with a transit theodolite in good adjustment, the observed altitude being 40° and the star being easterly. What is the standard time at instant of observation? The following information is extracted from the Greenwich Nautical Almanac:
Sirius R.A. 6 hrs. 40 min. 34.49 sec. Decl. s. 16° 34' 8.9".
Sidereal time at mean noon 7th, 15 hrs. 5 min. 44:79 sec.
Sidereal time at mean noon 8th, 15 hrs. 9 min. 41:34 sec.
Mean time transit of p 7th, 8 hrs. 52 min. 47.69 sec.
Mean time transit of p 8th, 8 hrs. 48 min. 51.78 sec.
1. Describe fully the methods adopted in measuring
the base lines of a geodetic survey.
2. How would you fix the positions of soundings
taken on a shoal, distant about 10 miles from a coast line having no prominent landmarks or hills of altitude exceeding 30 feet ?
3. A channel is 50 feet wide, the centre line is curved
to a radius of 120 feet, and the water in the centre flows with a velocity of 16 feet per second. What will be the difference of level at the two sides?
4. What are the chief points to be kept in view in
fixing the site of
(a) A bridge over a river subject to heavy floods.
(6) A cemetery 5. What is the virtual grade of a railway? Show by
an example how such a grade is drawn.
1. Define a structure and a machine. What branches
of physical science should be understood in order to design structures and machines properly?
2. On the Znin Railway, Germany, the gauge of which
is 2 feet, covered goods trucks 21 feet long, 6 feet high, and having the floor 1 foot from the ground, are in use. Compute the overturning wind pressure, the weight being 2.3 tons, and discuss the safety of these trucks under conditions such as obtain in Victoria.
3. Prove that a masonry dam of rectangular section is
no more stable than one having a right-angled triangular section of the same height and base. Explain how and why the latter form of dam is modified to suit practical conditions.
4. Draw carefully to scale bending moment and shear
diagrams of a beam 20 feet long, loaded with
(a) Supported at each end.