PSPCL AE 2012
⭕ A. Traverse Surveying
⭕ B. Geodetic Surveying
⭕ C. Plane Table Surveying
⭕ D. Hydrographic Surveying
📚 Explanation:
An Alidade is an instrument used in Plane Table Surveying for taking directions and drawing rays from a single station.
🔹 It consists of a sighting device (with or without telescope) mounted on a ruler used to draw lines of sight on the plotting sheet.
🔹 Helps in angular measurements and directly plotting the location of objects in the field.
🔹 Not used in traverse, geodetic, or hydrographic surveying methods.
An Alidade is an instrument used in Plane Table Surveying for taking directions and drawing rays from a single station.
🔹 It consists of a sighting device (with or without telescope) mounted on a ruler used to draw lines of sight on the plotting sheet.
🔹 Helps in angular measurements and directly plotting the location of objects in the field.
🔹 Not used in traverse, geodetic, or hydrographic surveying methods.
👉 Therefore, the correct answer is: C. Plane Table Surveying
Key Concepts about Alidade and Plane Table Surveying:
- Alidade: Used for taking sight lines and measuring angles
- Plane Table Surveying: Combines observation and plotting in the field
- Quick, economical, and ideal for small area surveys
- Requires a drawing board, tripod, alidade, and drawing tools
- Accuracy depends on the operator’s skill and visibility of objects
