Question

A leveling work was carried out along a falling gradient using a dumpy level and a levelling staff of 3 m length. The following successive readings were taken: 1.155, 2.74, 0.75. 1.79 m. What is the correct order of booking the four readings in the field book?(BS: back sight FS: foresight, IS: intermediate sight)

• A. BS, FS, BS, FS
• B. BS, IS, BS, FS
• C. BS, FS, IS, FS
• D. BS, IS, FS, BS

Answer 1

The correct option is A BS, FS, BS, FS

• Since, the ground is falling continuously staff readings should increase continuously

$1^{st}reading=BS=1.55m$

$2^{nd}reading>1streading=FS=2.74m$

$3^{rd}reading<2^{nd}reading=BS=0.75m$

$4^{th}reading=FS=1.79m$