MCQ Surveying Flashcards

The difference between steps when measuring downhill to get more precise results is?

Answer: Decreases with increase of slope

When measuring downhill to achieve more precise results, the length of each individual horizontal step or segment measured decreases as the slope increases. On steeper slopes, shorter horizontal measurements are taken to minimize errors caused by tape sag and to ensure the tape is held level. This reduction in the length of each step (the 'difference between steps') enhances the overall precision of the measurement.

A traverse leg's orthographical projection onto the reference meridian is referred to as

Answer: Latitude to the leg

In surveying, the orthographical projection of a traverse leg onto the reference meridian (the North-South line) is defined as the latitude of that leg. Latitude represents the change in the North-South coordinate from the beginning to the end of that specific traverse segment. Conversely, the projection onto the reference parallel (East-West line) is called the departure.

The flaw in a lens that causes white light rays to split into their constituent parts and go to multiple foci, creating a distorted and colored image is known as

Answer: Chromatic aberration

Chromatic aberration is a common lens flaw where different wavelengths of white light (colors) are refracted at slightly different angles, causing them to focus at varying points along the optical axis. This phenomenon results in a blurred image with noticeable color fringes around objects, as the lens cannot bring all colors to a single, sharp focal point.

A theodolite is when

Answer: All the above

A theodolite is a precision optical instrument used in surveying to measure horizontal and vertical angles. For accurate operation, it requires specific geometric relationships between its axes. These include the telescope axis being perpendicular to the transit axis, the axis of rotation being perpendicular to the transit axis, and ideally, all three axes (telescope, transit, and rotation) intersecting at the instrument's center. All these conditions are essential for proper functionality.

Random errors have a tendency to mount in proportion to

Answer: Square root of the number of operation involved

Random errors, which are unpredictable and fluctuate in magnitude and direction, tend to accumulate in proportion to the square root of the number of operations or measurements involved. This statistical principle is fundamental in error analysis, indicating that while individual random errors may partially cancel out, their cumulative effect grows, albeit at a slower rate than the direct number of operations.

In order to build a roadway (or railway)

Answer: Both longitudinal and cross sections are required

To effectively design and construct a roadway or railway, both longitudinal and cross sections are indispensable. Longitudinal sections provide a profile view along the center line, detailing elevation changes and gradients, which is crucial for drainage and grade design. Cross sections, taken perpendicular to the center line at intervals, illustrate the ground's shape and are essential for calculating earthwork volumes and designing the roadbed's width and slopes.

When a vernier's smallest division exceeds that of its primary scale, the vernier is referred as

Answer: Retrograde vernier

A retrograde vernier is a specific type of vernier scale where the smallest division on the vernier scale is larger than the smallest division on the main scale. Unlike a direct vernier, it is graduated in the opposite direction to the main scale. This design allows for precise readings by aligning the vernier marks with the main scale marks in a specific way.

The plumb line's normal is referred to as

Answer: Level line

A plumb line indicates the direction of gravity at a specific point, which is perpendicular to the local equipotential surface of the Earth's gravity field (the geoid). A level line is defined as a line that lies within a level surface and is therefore perpendicular to the direction of gravity (the plumb line) at every point along its length. Thus, the normal to the plumb line is a level line.

The two- and three-point problems are techniques for

Answer: Resection and orientation

The two-point and three-point problems are fundamental techniques in surveying used for both resection and orientation. Resection involves determining the unknown coordinates of an instrument station by observing known control points. Orientation then involves determining the direction of the reference line from that newly established instrument station, allowing for the accurate setup and continuation of a survey.

You may determine the earthwork's volume by using

Answer: All the above

The volume of earthwork, such as for excavations or embankments, can be accurately determined using several established methods. These include the trapezoidal rule (also known as the average end area method), the mean areas method, and the end areas method. All these techniques involve calculating the areas of cross-sections at intervals and then applying a formula to estimate the volume between them.

Select the appropriate statement from the list below.

Answer: All the above

All the statements accurately describe fundamental principles in surveying. For small-scale surveys, the Earth's curvature can be neglected, treating the surface as flat. However, for large-scale surveys, the curvature must be meticulously accounted for. Additionally, due to the Earth's spherical shape and local gravitational variations, plumb lines suspended at different points are not perfectly parallel but converge towards the Earth's center.