What is the function of the bubble tube in a levelling instrument?
A
To magnify the object B
To determine distance C
To ensure the instrument is level D
To rotate the telescope
Analysis & Theory
The bubble tube helps in leveling the instrument horizontally.
Which part of a levelling instrument is used to focus on the levelling staff?
A
Eyepiece B
Objective lens C
Focusing screw D
Tripod
Analysis & Theory
The focusing screw is used to sharpen the view of the staff.
What is the purpose of foot screws?
A
Support the tripod B
Level the base of the instrument C
Focus on object D
Read measurements
Analysis & Theory
Foot screws are used to level the instrument on the tripod.
Which part allows rotation of the telescope?
A
Tripod head B
Levelling head C
Vertical spindle D
Bubble tube
Analysis & Theory
The vertical spindle allows the telescope to rotate 360°.
What is the primary function of the levelling staff?
A
Support the instrument B
Rotate the telescope C
Measure elevation differences D
Level the instrument
Analysis & Theory
The staff measures the difference in elevation from the instrument's line of sight.