Map Work and Skills: Scale, Direction, Contours, and Location
What the Map Work and Skills section tests
Map reading, scale, direction, symbols, contours, latitude and longitude, and the location of Karnataka and India features. It is a skills section: you must show the method, not only the final name.
Core rules
- Scale has three forms: statement, representative fraction (RF), and graphical. 1 cm = 5 km is a statement scale; 1:500,000 is an RF.
- Directions: four cardinal and four intermediate. Grid north, true north, and magnetic north differ. A magnetic compass points to magnetic north, not true north.
- Contours join points of equal elevation: close contours mean a steep slope; widely spaced contours mean a gentle slope. Contour interval is the vertical distance between successive contours.
- Latitude runs east–west and measures north–south; longitude runs north–south and measures east–west. IST is based on 82°30′E.
- Symbols are conventional: blue for water, green for vegetation, black for cultural features, brown for contours.
Worked example
A map has RF 1:250,000. Two towns are 8 cm apart. Find the ground distance. 1 cm = 250,000 cm = 2.5 km. 8 cm × 2.5 km = 20 km. Convert centimetres to kilometres first, then multiply, and state the units.
Traps
Forgetting to convert cm to km; reading contour interval as horizontal distance; confusing latitude with longitude; using magnetic north as true north; naming a feature without locating it relative to a stated reference.