Which instrument is used for measurement of area in maps?

Question

Accepted Answer

The correct answer is Option 1: Planimeter.

Here's why:

*   **Planimeter:** A planimeter is a mechanical instrument specifically designed to measure the area of a two-dimensional shape, such as a region on a map. It works by tracing the outline of the area, and the instrument calculates the area enclosed within that boundary. This makes it the ideal tool for determining the area of features depicted on maps.

Now, let's explain why the other options are incorrect:

*   **Opisometer:** An opisometer (also known as a curvimeter or map measurer) is used to measure the length of curved lines, such as roads or rivers, on a map. It does *not* measure area.

*   **Pantograph:** A pantograph is a mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a second pen. If a line drawing is traced by the first point, an identical, enlarged, or miniaturized copy will be drawn by a pen fixed to the other. It's used for copying and scaling drawings, *not* for measuring area.

*   **Eidograph:** An eidograph is an instrument for copying drawings or maps on any scale. It is similar to a pantograph but allows for greater adjustment of the scale. Like the pantograph, it's used for copying and scaling, *not* for measuring area.

Therefore, the only instrument among the options specifically designed and used for measuring area on maps is the planimeter.