Civil Engineering - Surveying - Discussion

Discussion Forum : Surveying - Section 1 (Q.No. 30)
30.
While viewing through a level telescope and moving the eye slightly, a relative movement occurs between the image of the levelling staff and the cross hairs. The instrument is
correctly focussed
not correctly focussed
said to have parallax
free from parallax.
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
4 comments Page 1 of 1.

JAWAD said:   9 years ago
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and it is measured by the angle or semi-angle of inclination between those two lines.

MARATHA said:   7 years ago
Give the meaning of free parallax?

Pradip desai said:   7 years ago
Right @Jawad.

Uday said:   4 years ago
Without any parallax (error) is free parallax or free from parallax.

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