Question

A level has been found to be out of adjustment. When a two-peg test and adjustment were made, two stakes (A and B) were set 215 ft apart. When the instrument was set up midway between A and B, the rod readings were 4.26 on A and 5.15 on B. When the instrument was set up very close to A, the rod readings were 6.02 on A and 6.79 on B. With the instrument remaining near A, the crosshairs should be adjusted to a rod reading on B of most nearly: 44. (A) 6.67 (B) 6.79 (C) 6.85 (D) 6.91

Answer 1

When instrument at midway True difference When instrument at A Apparent difference H H5.15-4.260.89 (B being lower) 6.79-6.02 0.77 (B being lower) = The amount of inclination = 0.89-0.77-0.12 Adjusted reading on B 6.79 + 0.12 = 6.91 Check: True difference = 6.91-6.02