Question

In levelling, correction for curvature of the earth is always:

• A. {Positive}
• B. {Zero}
• C. {Negative}
• D. {Infinity}

Hint:

Curvature correction in levelling is always negative, as the Earth's surface curves away from the line of sight.

Answer 1

The Correct Option is C

Step 1: In levelling, the curvature of the Earth causes a systematic error, making objects appear lower than they actually are. Step 2: The correction formula is: \[ C_c = - 0.0785 D^2 \] where \( D \) is the distance in kilometers. The negative sign indicates that the correction is downward. Thus, the correct answer is (C) Negative.