Question

In levelling, error due to earth’s curvature is to be corrected using:

(a) Cc=0.0673D^2

(b) Cc=0.0112D^2

(c) Cc=0.0136D^2

(d) Cc=0.0785D^2

I got this question in examination.

I'm obligated to ask this question of Methods of Levelling topic in section Basic Surveying of Basic Civil Engineering

Answer 1

The correct option is (d) Cc=0.0785D^2

Explanation: Correction for earth’s curvature and refraction is to be applied. Cc is given by 0.0785D^2. Combined correction Cc – Cr is given by 0.0673D^2.