Question

Theodolite is an instrument used for:
1. Tightening the capstan-headed nuts of level tube
2. measurement of vertical angles only
3. measurement of both horizontal and vertical angles
4. measurement of horizontal angles angle

Answer 1

Correct Answer - Option 3 : measurement of both horizontal and vertical angles

Concept:

Theodolite:

• A theodolite is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes.​

• It consists of a moveable telescope mounted so it can rotate around horizontal and vertical axes and provide angular readouts.

Tyes of theodolite:

1. Transit theodolite:

A theodolite is called a transit theodolite when its telescope can be transited i.e revolved through a complete revolution about its horizontal axis in the vertical plane.

2. Non-transit theodolite:

A theodolite is called a transit theodolite when its telescope cannot be transited. They are inferior in utility and have now become obsolete.

Uses of theodolite:

• Measuring horizontal and vertical angles.
• Locating points on a line
• Prolonging survey lines 
• Finding difference of level
• Setting out grades
• Ranging curves
• Tacheometric Survey