# Surveying Questions and Answers – Theory of Direct Levelling(Spirit Levelling)

This set of Surveying Quiz focuses on “Theory of Direct Levelling(Spirit Levelling)”.

1. A level provides a vertical line of sight, a line tangential to a Level surface at the point where the instrument stands.
a) True
b) False

Explanation: A level provides a horizontal line of sight. A line tangential to a Level surface at the point where the instrument stands.

2. The theory of direct levelling neglects _____
a) curvature of the earth
b) refraction
c) both curvature of earth and refraction

Explanation: Neglecting the curvature of earth and refraction, therefore, the theory of direct levelling is very simple. Radius of the earth doesn’t have any criteria.

3. Which of the following methods of spirit levelling is, levelling the object of which is solely to determine the difference in elevation of two points regardless of the horizontal position of the points with respect to each other?
a) Profile levelling
b) Cross levelling
c) Differential levelling
d) Reciprocal levelling

Explanation: Differential levelling is the method of direct levelling the object of which is solely to determine the difference in elevation of two points regardless of the horizontal position of the points with respect to each other. This type of levelling is also called fly levelling.

4. Fly levelling is another name of _____
a) Profile levelling
b) Cross levelling
c) Differential levelling
d) Reciprocal levelling

Explanation: Differential levelling is the method of direct levelling the object of which is solely to determine the difference in elevation of two points regardless of the horizontal position of the points with respect to each other. This type of levelling is also called fly levelling.

5. Which of the following methods of spirit levelling is, levelling the object of which is solely to determine the elevations of points at measured intervals along a given line?
a) Profile levelling
b) Cross levelling
c) Differential levelling
d) Reciprocal levelling

Explanation: Profile levelling is a direct levelling the object of which is solely to determine the elevations of points at measured intervals along a given line. It is done in order to obtain a profile of the surface along that line.
Sanfoundry Certification Contest of the Month is Live. 100+ Subjects. Participate Now!

6. Cross sectioning is the process of taking levels on each side of a main line tangential to that line.
a) True
b) False

Explanation: Cross sectioning is the process of taking levels on each side of the main line at right angles to that line. It is also called cross levelling.

7. Which of the following methods of spirit levelling is, levelling in which the difference in elevation between two points is accurately determined by two sets of reciprocal observations?
a) Profile levelling
b) Cross levelling
c) Differential levelling
d) Reciprocal levelling

Explanation: Reciprocal levelling is the method of levelling in which the difference in elevation between two points is accurately determined by two sets of reciprocal observations. It is done only when it is not possible to set up the level between the two lines.

8. Which of the following methods of spirit levelling is, levelling in which the degree of precision required is too great to be attained by ordinary methods?
a) Profile levelling
b) Precise levelling
c) Differential levelling
d) Reciprocal levelling

Explanation: Precise levelling is the levelling in which the degree of precision required is too great to be attained by ordinary methods. Therefore, special equipment or special precaution or both are necessary to eliminate all sources of errors as far as possible.

9. What is the height of instrument, if elevation of benchmark is 200.852 m, back sight is 2.324 m, fore sight is 1.836 m?
a) 213.176
b) 203.176
c) 211.340
d) 201.340

Explanation: Height of instrument is obtained by adding the elevation of benchmark and back sight. Here, 201.852 + 2.324 = 203.176 m.

10. What is the elevation of a point, if the elevation of a benchmark is 200.852 m, back sight is 2.324 m, foresight is 1.836 m?
a) 213.176
b) 203.176
c) 211.340
d) 201.340

Explanation: Elevation of a point is obtained by subtracting the elevation of benchmark and foresight. Here, 201.852 – 1.836 = 201.340 m.

Sanfoundry Global Education & Learning Series – Surveying.

To practice all areas of Surveying for Quizzes, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]