NICET - Highway Construction Inspection Practice Exam

Which tool is used to determine the area of a topographic map?

1. Planimeter

2. Water Level

3. Topographical Gauge

4. Measuring Tape

The correct answer is: Planimeter

The planimeter is the correct tool for determining the area of a topographic map because it is specifically designed to measure the area of irregular shapes, which is often required in topographic analysis. When using a planimeter, an operator traces the perimeter of the area of interest, and the device calculates the area based on the path traced. This is particularly useful in topographic mapping, where the shapes are seldom regular and may include various elevations and contours. While the water level is a tool for establishing level points in surveying, it does not provide measurements for area calculations. A topographical gauge is not a standard tool used widely in surveying or for measuring areas directly on maps. Moreover, measuring tape can measure linear distances but lacks any method to calculate area directly from the dimensions of shapes found on a map. Therefore, in the context of determining area from a topographic map, the planimeter stands out as the appropriate choice.