Horizontal Stadia Sights

PROBLEM:
An engineer’s level with a stadia constant of 0.30m was set – up on the line between two – points A, B, and the following hair readings were observed.
Rod Position Hair Readings
U(a) M(c) L(b)
A 1.33m 1.175m 1.02m
B 1.972m 1.854m 1.736m

Solve the ff.:
S= stadia interval factor
HD= horizontal distance from the level at the rod A
HD2= horizontal distance from the level at the rod B
Lab= length of the AB

Formula:
S = (a – b)
HD = Ks + C
HD2= Ks2 + C
Lab = d + d2

Given:
C = 0.30m
K = 95.5m

Solution for A & B:
S = (a – b)
= (1.33 – 1.02)
= 0.31m
HD = Ks + C
= (95.5) (0.31) + 0.30
= 29.605 + 0.30
= 29.91m
S2 = (1.972 – 1.736)
= 0.24m
HD2 = 95.5(0.24) + 0.30
= 22.92 + 0.30
= 23.22m
Lab = d + d2
= 29.91m + 23.22m
= 53.13m