A globe is the most accurate small model of Earth because it keeps the planet’s round shape. A flat map is easier to carry, print, measure, and use on a screen, but it must stretch or cut Earth’s curved surface to lie flat. This transformation is called map projection, and it changes shapes, areas, distances, or directions in different ways.
Learning how maps work helps students read locations, compare regions, and understand data about Earth.
Key Facts
- Latitude lines run east to west and measure degrees north or south of the Equator.
- Longitude lines run north to south and measure degrees east or west of the Prime Meridian.
- Coordinates are written as latitude, longitude, such as 34°N, 118°W.
- Map scale compares map distance to real distance, such as 1 cm = 100 km.
- Distance on map x scale factor = real distance.
- No flat map can show Earth perfectly because a sphere cannot be flattened without distortion.
Vocabulary
- Globe
- A globe is a round model of Earth that shows relative shapes, directions, and distances with less distortion than a flat map.
- Map projection
- A map projection is a method for showing Earth’s curved surface on a flat map.
- Latitude
- Latitude is the angular distance north or south of the Equator, measured in degrees.
- Longitude
- Longitude is the angular distance east or west of the Prime Meridian, measured in degrees.
- Scale
- Scale is the relationship between a distance on a map and the matching distance in the real world.
Common Mistakes to Avoid
- Treating every flat map as perfectly accurate is wrong because all projections distort at least one property, such as area, shape, distance, or direction.
- Mixing up latitude and longitude is wrong because latitude measures north or south from the Equator, while longitude measures east or west from the Prime Meridian.
- Ignoring the map scale is wrong because the same line length can represent very different real distances on different maps.
- Assuming north is always the top without checking the compass rose is wrong because some maps are rotated for local use or design clarity.
Practice Questions
- 1 A map scale says 1 cm = 50 km. If two cities are 7 cm apart on the map, how far apart are they in real life?
- 2 A student measures a river as 12 cm long on a map with a scale of 1 cm = 25 km. What real-world length does the map show for the river?
- 3 A world map shows Greenland almost as large as Africa, but a globe shows Africa is much larger. Explain how map projection distortion can cause this difference.