Question

If the altitude bubble is provided both on the index frame as well as on the telescope of a theodolite, then the instrument is levelled with reference to the:

• A. altitude bubble on the telescope
• B. altitude bubble on the index frame, if it is to be used as a level
• C. altitude bubble on the telescope, if it is to be used as a level
• D. laser principle

Hint:

Use index frame bubble when theodolite serves as a level.

Answer 1

The Correct Option is B

If both index frame and telescope have altitude bubbles, the instrument is levelled with respect to the index frame when the theodolite is used as a level. This ensures the correct alignment of the line of sight.