Which of the following statements is/are true regarding the angular measurements using a theodolite? i. In the Method of Repetition, a series of angles around a point are measured successively for many times. ii. In the Method of Reiteration, a series of angles around a point are measured successively to close a polygon.
- AOnly (i)
- BOnly (ii)
- CBoth (i) and (ii)
- DNeither (i) nor (ii)Correct
Solution
Concept
Angular measurement methods using a theodolite
Formula
NONE
Step-by-step solution
1. In the Method of Repetition, a single angle is measured multiple times cumulatively on the instrument scale to refine precision. 2. In the Method of Reiteration, multiple angles radiating from a central point are measured successively to complete the horizon. 3. Therefore, both statements i and ii present incorrect definitions. Answer: D
Explanation
In the Method of Repetition, a single angle is measured multiple times sequentially using the same station to improve precision rather than measuring a series of different angles. In the Method of Reiteration, multiple angles around a central point are measured sequentially to close the horizon at a single station, not to close a polygon traverse. Because both provided statements misrepresent these surveying procedures, option D is correct.
Why the other options are wrong
A) Statement (i) incorrectly describes repetition, as repetition measures a single angle multiple times. B) Statement (ii) incorrectly describes reiteration, which involves measuring several angles at a station with a single horizon closure. C) Both statements (i) and (ii) misdescribe the definitions of the repetition and reiteration methods.
Shortcut
Repetition = 1 angle multiple times; Reiteration = multiple angles around a point (Neither statement is true).
Common mistake
Selecting Option C by failing to notice that the definitions for the methods of repetition and reiteration are inaccurately stated.
Correct answer: D) Neither (i) nor (ii)