Question

Which type of map is made by projecting points and lines from a globe onto a cone? A. Mercator projection B. conic projection C. Robinson projection D. geologic map

Short answer

B: conic projection

Step-by-step solution

Understanding the Problem

The exercise asks which type of map involves projecting points and lines from a globe onto a cone. This requires understanding different types of map projections and their unique characteristics.

Identifying Characteristics of Map Projections

Review the given options: - Mercator projection: Projects onto a cylinder, not a cone. - Conic projection: Projects onto a cone, matching the problem description. - Robinson projection: A compromise map, not specifically using a cone. - Geologic map: Shows Earth's features, not related to cone projection.

Evaluating the Options

From the definitions, only the conic projection involves projecting onto a cone. This aligns with the problem's description of mapping points and lines from a globe onto a cone.

Selecting the Correct Answer

Since the conic projection is the correct match based on the evaluation, we select option B: conic projection.

Key concepts

Conic Projection

A conic projection is a type of map projection where the surface of the globe is projected onto a cone, which is then unrolled into a flat plane. This technique is particularly useful for mapping mid-latitude regions that have an east-west orientation, such as North America and Europe. These areas tend to have minimal distortion in size and distance when using conic projections, a significant advantage for geographic analysis.
Some key characteristics of conic projections include:

• The lines of latitude are represented as arcs or concentric circles on the map.
• The lines of longitude are straight, radiating lines that converge at one point, typically beyond the globe.
• A standard parallel, or set of parallels, can be selected to minimize distortion along specific lines of latitude.

Common forms of conic projections include the Lambert Conformal Conic, which is optimal for aeronautical charts, and the Albers Equal-Area Conic, often used for thematic maps due to its size-preserving properties.

Geographic Coordinate System

The geographic coordinate system is the framework used to pinpoint any location on Earth using a set of numerical coordinates. These coordinates are given in latitude and longitude, which measure the distance from the equator and the prime meridian, respectively. This system is vital for creating accurate representations of the Earth on a flat map.
The Earth is divided into:

• Lines of latitude, or parallels, that run east-west and indicate how far north or south a point is from the equator.
• Lines of longitude, or meridians, that run north-south and measure the distance east or west of the prime meridian, which is situated in Greenwich, England.

By combining these two angles, we get a precise location on the Earth's surface, allowing for detailed mapmaking and navigation. In modern applications, GPS (Global Positioning System) technology utilizes this coordinate system to provide real-time location data.

Cylindrical Projection

In a cylindrical projection, the globe is projected onto a cylinder that is then unwrapped into a flat surface. This method straightens the globe's surface, causing the meridians to appear as equally spaced vertical lines, and the parallels of latitude as horizontal lines. This projection is notably used in world maps due to its ability to represent the entire Earth's surface.
Some distinctive features of cylindrical projections include:

• Lines of latitude are all parallel to one another, appearing as evenly spaced horizontal lines across the map.
• Lines of longitude, unlike on a globe, do not converge and are equidistant throughout the map.
• This projection is often criticized for its distortion of areas closer to the poles, making landmasses like Greenland appear much larger than they actually are.

The Mercator projection is the most famous type of cylindrical projection, primarily used for navigation because it preserves angles and directions, making it ideal for sea travel.

Types of Maps

Maps come in various types, each serving specific purposes by emphasizing different data aspects. Choosing the correct map type is crucial depending on the information you want to convey or analyze. Some widely recognized map types include:

• Physical maps - These maps highlight natural features like mountains, rivers, and lakes, providing a view of the physical landscape.
• Political maps - These focus on man-made entities, such as countries, states, and cities, clearly delineating their boundaries.
• Thematic maps - Designed to emphasize specific themes or subjects, such as population density or climate zones, useful for visualizing complex data.
• Topographic maps - Featuring contour lines, these maps show elevation changes and terrain details, valuable for hikers and engineers.

Each map type employs different projection techniques depending on its purpose. Understanding these types helps you select the appropriate map for educational, navigational, or analytical applications.