321. Which of the following contour line patterns represents a ridge?
a) Concentric circles
b) Alternating short and long dashes
c) Hatched loops
d) Straight parallel lines
View Answer
Correct answer: d) Straight parallel lines
Explanation: Contour lines that form straight parallel lines represent ridges or elevated features.
322. The contour line pattern that represents a valley is:
a) Concentric circles
b) Alternating short and long dashes
c) Hatched loops
d) Straight parallel lines
View Answer
Correct answer: c) Hatched loops
Explanation: Contour lines that form hatched loops represent valleys or low-lying areas.
323. What is contouring by interpolation?
a) Estimating elevations between known contour lines
b) Determining elevations using aerial photographs
c) Creating contour lines based on survey measurements
d) Identifying depressions and closed loops on a map
View Answer
Correct answer: a) Estimating elevations between known contour lines
Explanation: Contouring by interpolation involves estimating elevations between known contour lines using mathematical or graphical techniques.
324. In contouring, the process of “closing the contours” refers to:
a) Completing the survey field book
b) Connecting contour lines to form closed loops
c) Calculating the contour interval
d) Leveling the survey equipment
View Answer
Correct answer: b) Connecting contour lines to form closed loops
Explanation: Closing the contours in contouring refers to connecting contour lines to form closed loops, which represent depressions or elevated features.
325. What is the purpose of index contours on a topographic map?
a) To mark the location of important landmarks
b) To indicate areas of dense vegetation
c) To provide elevations at regular intervals
d) To show the magnetic declination
View Answer
Correct answer: c) To provide elevations at regular intervals
Explanation: Index contours on a topographic map are labeled with elevation values and provide elevations at regular intervals, typically at every fifth contour line.
326. Which of the following contour line patterns represents a saddle or a low point between two higher points?
a) Concentric circles
b) Alternating short and long dashes
c) Hatched loops
d) Straight parallel lines
View Answer
Correct answer: a) Concentric circles
Explanation: Contour lines that form concentric circles represent a saddle or a low point between two higher points.
327. What is the purpose of contouring in civil engineering?
a) To determine property boundaries
b) To plan road alignments
c) To calculate the volume of earthwork
d) To locate underground utilities
View Answer
Correct answer: c) To calculate the volume of earthwork
Explanation: Contouring in civil engineering is used to determine the elevation of the ground surface and calculate the volume of earthwork required for construction projects.
328. Which of the following instruments is commonly used for contouring?
a) Total station
b) Theodolite
c) Leveling rod
d) GPS receiver
View Answer
Correct answer: a) Total station
Explanation: A total station, which combines electronic distance measurement (EDM) and angle measurement capabilities, is commonly used for accurate and efficient contouring.
329. When contour lines cross a stream or a river, they form:
a) Concentric circles
b) Straight parallel lines
c) Alternating short and long dashes
d) “V” shapes pointing upstream
View Answer
Correct answer: d) “V” shapes pointing upstream
Explanation: When contour lines cross a stream or a river, they form “V” shapes pointing upstream, indicating the direction of flow.
330. Which of the following methods is used for contouring in mountainous terrain?
a) Photogrammetry
b) Resection
c) Trilateration
d) Triangulation
View Answer
Correct answer: d) Triangulation
Explanation: Triangulation, using a network of interconnected triangles, is often used for contouring in mountainous terrain due to the challenges posed by steep slopes and rugged topography.
