In 'Water drop method' the diameter of water drop should be

A. 4.5 mm

B. 30 mm

C. 30 cm

D. 4.7 mm

Answer: Option D

Solution(By Examveda Team)

In the 'water drop method', the diameter of the water drop should be 4.7 mm.
A drop or droplet is a small column of liquid, bounded completely by free surfaces.
Drop testing is used to check the volume of water loss from a reservoir to identify maintenance requirements and to meet the requirements of regulatory authorities.