CST Level 1 Land Surveyor Certification Practice

A Left Deflection Angle is defined as:

1. Measured clockwise from the rear line

2. Measured counterclockwise from the extension of the rear line to the forward line

3. An angle measured vertically

4. A negative angle measurement

The correct answer is: Measured counterclockwise from the extension of the rear line to the forward line

The definition of a Left Deflection Angle is most accurately described as being measured counterclockwise from the extension of the rear line to the forward line. This is significant in surveying because it provides a consistent method for determining the direction of angles in relationship to a given reference line, which is essential for creating accurate maps and layouts. When determining angles in land surveying, it is crucial to observe the direction in which the measurements are taken. By establishing that the angle is measured counterclockwise, this definition ensures clarity in communication and accuracy in angle calculations. This orientation is typically used in survey calculations to standardize the way angles are documented, ensuring that everyone following the same surveying practices will interpret the angles in the same manner. The other options do not accurately describe the Left Deflection Angle as they relate to different aspects of angle measurement or definitions used in surveying. While they may pertain to angles in some context, they do not convey the specific counterclockwise measurement from the extension of the rear line that characterizes a Left Deflection Angle.