Explanation:
All three statements are correct. The directions of plumb lines suspended at different points in a survey are not strictly parallel. This is because gravity varies slightly depending on location and local geology. In surveys of small extent, the effect of curvature may be ignored and the level surface of the earth is assumed as horizontal. For small areas, the curvature of the Earth is negligible, and it's practical to assume a flat, horizontal surface. In surveys of large extent, the effect of curvature of the earth must be considered. For large-scale surveys, especially over long distances, the curvature of the Earth becomes significant and must be taken into account for accurate measurements.
So, the correct option is all the above.
Explanation:
In a retrograde vernier scale, the smallest division of the vernier scale is longer than the smallest division of the main or primary scale. This means that the vernier scale readings move in the opposite direction compared to the main scale.
Explanation:
In surveying and cartography, the orthographical projection of a traverse leg upon the reference meridian is referred to as the "Latitude to the leg". This is a crucial concept in the calculation of coordinates and distances in traverse surveys.
Explanation:
When measuring downhill, the slope of the terrain affects the accuracy of the measurement. In order to obtain better accuracy, it's important to decrease the distance between steps. This is because when you're going downhill, the distance you cover in each step is longer due to the slope. By taking shorter steps, you can more accurately measure the true horizontal distance between two points. If you take longer steps, you may overestimate the distance. In summary, as the slope increases, you should take shorter steps to get a more accurate measurement. This is why the distance between steps decreases with an increase in slope.
Explanation:
Random errors, also known as statistical errors, are caused by unpredictable fluctuations in experimental measurements. They tend to follow a normal distribution around the true value of the measurement. In many cases, these errors tend to accumulate according to the square root of the number of operations involved. This is a consequence of the mathematical properties of random variables. So, the correct option is Square root of the number of operation involved.
Explanation:
The line that is normal (perpendicular) to the plumb line (which points directly towards the center of the Earth due to gravity) is known as a "Level Line". It is used as a reference for determining horizontal or level surfaces.
Explanation:
The Two Point Problem: This is a method used to determine the location of an unknown point by sighting two known points from the unknown location. It is commonly used in situations where it's difficult to directly measure distances. The Three Point Problem: This is also a method used to determine the location of an unknown point, but it involves sighting three known points from the unknown location. This provides more redundancy and can lead to more accurate results. Both of these methods, the two point problem and the three point problem, are techniques used in surveying for both resection (determining the location of an unknown point) and orientation (determining the direction or position of a line or feature).
Explanation:
Chromatic aberration is the optical phenomenon where a lens or a prism fails to focus all colors to the same convergence point. This results in different colors (or wavelengths) of light being focused at different distances from the lens, leading to a blurred and colored image.
Explanation:
In the construction of a highway or railway, both longitudinal and cross sections are required.
Explanation:
In a theodolite:
The telescope axis is perpendicular to the transit axis: This is true. The telescope can be rotated around an axis that is perpendicular to the transit axis. The axis of rotation is perpendicular to the transit axis: This is also true. The theodolite can be rotated around an axis that is perpendicular to the transit axis. The telescope axis, the transit axis, and the rotation axis pass through the center of the theodolite: This is true. The three axes are designed to intersect at the center of the theodolite. Therefore, all of the statements are correct, making option All the above" the correct answer.
Explanation:
Volume of earthwork refers to the quantity of material (earth, rock, etc.) that needs to be excavated or filled to achieve a certain construction goal, like building a road or a dam. Different methods can be used to calculate the volume of earthwork, depending on the shape of the terrain and the requirements of the project. All of these methods are used in various situations depending on the specifics of the project and the shape of the terrain. So, the correct answer is all the above.
