1. What is the lateral distance of an object or ground feature measured from a survey line?
a) Offset
b) Perpendicular distance
c) Side distance
d) Perpendicular offset
Explanation: An offset is the lateral distance of an object or ground feature measured from a survey line. When the angle of the offset is 90°, it is called perpendicular offset.
2. An offset is laid out 6° from its true direction on the field. Find the resulting displacement of the plotted point on the paper in a direction parallel to the chain line? (Given the length of offset is 10 m and scale is 5 m to 1 cm)
a) 0.209 cm
b) 0.260 cm
c) 0.0109 cm
d) 0.910 cm
Explanation: Distance parallel to the chain = lsin∆/ s = 10 sin 6°/ 5 = 0.209 cm.
3. An offset is laid out 6° from its true direction on the field. Find the resulting displacement of the plotted point on the paper in a direction perpendicular to the chain line? (Given length of offset is 10 m and scale is 5 m to 1 cm)
a) 0.209 cm
b) 0.260 cm
c) 0.0109 cm
d) 0.910 cm
Explanation: Distance perpendicular to the chain = l(1 – cos∆)/s = 10 (1 – cos 6°)/5. By simplifying we get 0.0109 cm.
4. An offset is laid out 1° 30′ from its true direction on the field. Find the degree of accuracy with which the offset should be measured so that the maximum displacement of the point on the paper from both sources may be equal?
a) 1 in 38
b) 1 in 39
c) 1 in 36
d) 1 in 37
Explanation: Displacement due to angular error is lsin∆. Displacement due to linear error l/r. Equating both r = 38.20. Hence, the offset should be measured with an accuracy of 1 in 39.
5. An offset is measured with an accuracy of 1 in 40. If the scale of plotting is 1 cm = 20 m, find the limiting length of the offset so that the displacement of the point on the paper from both sources of error may not exceed 0.25 mm?
a) 14.10 m
b) 14.14 m
c) 14.40 m
d) 14.44 m
Explanation: The total displacement of the paper = √2 l /rs. From this we can simply for l = (0.025/√2)*40*20 = 14.14 m.
6. What triangles are generally preferred to get good results in plotting?
a) Isosceles
b) Obtuse angled
c) Equilateral
d) Acute angle
Explanation: To get good results in plotting, the frame work should consist of triangles which are as nearly equilateral as possible.
7. The line must run through level ground as possible is the condition to be fulfilled by survey lines or survey stations.
a) True
b) False
Explanation: The survey stations should be so selected that a good system of lines is obtained fulfilling the following conditions such as survey stations must be mutually visible, the lines must run through level ground as possible etc
8. The main lines should form well-conditioned triangles is the condition to be fulfilled by survey lines or survey stations.
a) True
b) False
Explanation: The survey stations should be so selected that a good system of lines is obtained fulfilling the following conditions such as the lines must run through the level ground as possible, the main lines should form well-conditioned triangles etc.
9. Survey lines must be as few as possible is the condition to be fulfilled by survey lines or survey stations.
a) True
b) False
Explanation: The survey stations should be so selected that a good system of lines is obtained fulfilling the following conditions such as the lines must run through the level ground as possible, survey lines must be as few as possible so that the frame work can be plotted conveniently, the main lines should form well-conditioned triangles etc.
10. As far as possible main survey lines should pass through the obstacles to get know how many obstacles present.
a)True
b) False
Explanation: The survey stations should be so selected that a good system of lines is obtained fulfilling the following conditions such as the lines must run through the level ground as possible, as far as possible, the main survey lines should not pass through obstacles.