Question

Ashwin is required to take the measurement of a wooden box. Which of the following should be the proper position of his eye for taking the reading?

(A)
(B)
(C)
(D) [1 Mark]

Answer 1

Ashwin must position his sight in such a way that his line of sight is perpendicular to the scale-readings. This is achieved by placing his eye exactly vertically above the scale.
If this is not ensured, then he will observe a parallax error leading to an error in the measurement.

Hence option C is correct.
[1 Mark]