Correct Answer: D. Working from part to whole
Solution:
The fundamental principle is "working from the whole to the part" to prevent the accumulation of errors. Working from part to whole is incorrect and would magnify errors throughout the survey. The other statements are correct applications or principles of surveying.
Correct Answer: D. 35, 80, 65
Solution:
A well-conditioned triangle is one where no angle is too small (less than 30°) or too large (greater than 120°). This ensures a sharp and accurate intersection when plotting. In option D, all angles (35°, 80°, 65°) are within the ideal range. The other options contain angles that are either too acute or too obtuse, making them ill-conditioned.
Correct Answer: D. 10
Solution:
For a direct vernier, the least count (LC) is the difference between one smallest division on the main scale (s) and one smallest division on the vernier scale (v). The relationship is given by the formula: LC = s / n, where 'n' is the number of divisions on the vernier scale.
Given: s = 0.5 mm, LC = 0.05 mm.
n = s / LC = 0.5 / 0.05 = 10.
Therefore, 10 divisions are required on the vernier scale.
Correct Answer: D. 120 m
Solution:
This problem implies the surveyor calculated a ground distance of 60 m by measuring a distance on the map and incorrectly using an RF of 1:50. The map's actual RF is 1:100.
1. First, find the distance on the map:
Calculated Distance = Map Distance / Wrong RF => 60 m = Map Distance / (1/50).
Map Distance = 60 / 50 = 1.2 m.
2. Now, use the correct RF to find the true ground distance:
Correct Distance = Map Distance / Correct RF = 1.2 m / (1/100) = 1.2 * 100 = 120 m.
Correct Answer: A. 250
Solution:
In plane surveying, the Earth's curvature is not taken into account. This is a valid assumption for small areas. The generally accepted upper limit for treating a survey as 'plane' is about 250 square kilometers. For areas larger than this, geodetic surveying, which accounts for the Earth's spheroidal shape, is necessary to maintain accuracy.
Correct Answer: D. 1 : 2,500
Solution:
A map scale is a ratio of map distance to ground distance. A "smaller" scale means the ratio is smaller. For example, 1:2,500 is equivalent to the fraction 1/2500, while 1:100 is 1/100. Since 1/2500 is a smaller number than 1/100, 1:2,500 is the smallest scale. Small-scale maps cover large areas with less detail.
Correct Answer: D. It is inversely proportional to square of F
Solution:
The relationship for corrected area based on a shrunk map is: Correct Area = Measured Area / (Shrunk Factor)². Therefore, the corrected area is inversely proportional to the square of F.
Correct Answer: A. 1 : 500
Solution:
A "larger" scale has a smaller denominator. The ratio 1/500 is a larger number than 1/1000 or 1/50000. Large-scale maps show more detail for a smaller area.
Correct Answer: D. 260 km²
Solution:
For surveys covering an area greater than approximately 250-260 km², the curvature of the Earth becomes significant and must be accounted for to maintain accuracy. This type of survey is known as geodetic surveying.
Correct Answer: A. Geodetic surveying
Solution:
Geodetic surveying is the method used for large areas where the Earth's spherical shape is considered. In contrast, plane surveying assumes the Earth is flat and is only suitable for smaller areas.
Correct Answer: C. graduations increase in the same direction in which graduations of the main scale increase
Solution:
A direct vernier scale is constructed so that its divisions are slightly smaller than the main scale divisions, and they are marked in the same direction. This is the most common type of vernier scale.
Correct Answer: A. 10 mm
Solution:
The difference between the length of a long arc and its corresponding chord on the Earth's surface is approximately 1 cm (10 mm) for every 18.2 km of length. This is a standard value used in geodetic calculations to account for the Earth's curvature.
Correct Answer: B. The curvature of the earth is considered
Solution:
The fundamental distinction between plane and geodetic surveying is the treatment of the Earth's shape. Plane surveying assumes a flat surface, while geodetic surveying accounts for its curvature. While large areas often necessitate geodetic methods, the consideration of curvature is the defining technical difference.
Correct Answer: C. Units, tenths and hundredths can be shown
Solution:
A diagonal scale is a graphical tool used for precise measurements. By using the principle of similar triangles, it can represent three different units or a main unit and its two subdivisions (e.g., meters, decimeters, and centimeters). This allows for reading units, tenths, and hundredths of a unit.
Correct Answer: B. 1 / 1,000
Solution:
To calculate the Representative Fraction (RF), the units must be the same.
First, convert 10 meters to centimeters: 10 m * 100 cm/m = 1,000 cm.
The scale is 1 cm on the map to 1,000 cm on the ground.
Therefore, the RF is 1 / 1,000.