Technical Terms (Map Reading) MCQs Quiz | Class 9
This quiz is for Class IX students studying the subject NCC (Code 076). It covers Unit 3 of the Army syllabus, “Map Reading,” focusing on the topic of Technical Terms. You will be tested on common terms used in topographical sheets. After completing the 10 questions, submit your answers to see your score and download a PDF of your answer sheet.
Understanding Technical Terms in Map Reading
Map reading is a crucial skill in the NCC, especially for the Army wing. It involves understanding and interpreting topographical maps, which use specific technical terms, symbols, and conventions. Mastering these terms is the first step towards effective navigation and tactical planning. This section provides a detailed overview of the key concepts covered in the quiz.
Key Concepts in Topographical Maps
Topographical maps provide a detailed, two-dimensional representation of a three-dimensional surface. Here are the fundamental terms you must know:
1. Grid System
A network of horizontal and vertical lines printed on a map, used for locating points.
- Eastings: The vertical lines that run from top to bottom. Their value increases as you move from West to East.
- Northings: The horizontal lines that run from left to right. Their value increases as you move from South to North.
- Grid Reference (G.R.): A unique address for any point on the map, given by its Easting and Northing values. A four-figure G.R. identifies a square, while a six-figure G.R. pinpoints a location within that square with more precision. The rule is “Along the corridor, then up the stairs” (Eastings first, then Northings).
2. Contours and Relief
Relief refers to the shape of the land surface, including its height and steepness.
- Contour Lines: These are imaginary lines on a map that connect points of equal elevation (height) above sea level.
- Contour Interval: The constant vertical distance between two adjacent contour lines.
- Interpretation: Closely spaced contours indicate steep terrain, while widely spaced contours show a gentle slope or flat land.
3. Scale
The scale of a map is the ratio between a distance on the map and the corresponding distance on the ground. For example, a scale of 1:50,000 means that 1 unit of measurement on the map (like 1 cm) represents 50,000 of the same units on the ground.
4. Bearings and Norths
A bearing is the angle measured in a clockwise direction from a fixed reference point, which is usually North.
- True North: The direction of the North Pole.
- Grid North: The direction of the vertical grid lines (Eastings) on a map.
- Magnetic North: The direction a compass needle points to.
- Magnetic Declination: The angular difference between True North and Magnetic North.
5. Conventional Signs
These are standard symbols used on a map to represent natural and man-made features on the ground, such as temples, forts, roads, bridges, and rivers. This allows a lot of information to be packed into a small space without cluttering the map with text.
| Feature | Conventional Sign Description |
|---|---|
| Temple | A small square with a flag on top. |
| Metalled Road | Two parallel solid red lines. |
| Unmetalled Road | Two parallel broken red lines. |
| River (Dry) | A blue line with black dots inside. |
| Fort | A solid black square with battlements. |
Quick Revision Points
- Always read Grid References by stating the Easting value first, followed by the Northing value.
- Steep slopes are shown by contour lines that are very close together.
- A six-figure G.R. is more accurate than a four-figure G.R.
- The scale helps convert map distances to actual ground distances.
- Bearings are always measured clockwise from North.
Practice Questions
- What is the term for the height of a point above mean sea level?
- If contour lines form a closed loop with decreasing height towards the center, what feature does it represent?
- What is the main purpose of a service protractor in map reading?
- What does ‘dead ground’ refer to on a map?
- How is a benchmark represented on a survey map?
