question_answer

A long cylindrical vessel is half filled with a liquid. When the vessel is rotated about its own vertical axis, the liquid rises up near the wall. If the radius of vessel is 5 cm and its rotational speed is 2 rotations per second, then the difference in the heights between the centre and the sides, in cm, will be-                              [JEE Main 12-Jan-2019 Evening]

A)   0.4                 

B)        2.0

C)   0.1                 

D)        1.2

Correct Answer: D

Solution :

[b] The linear speed of the liquid at the sides is . So, the difference in height is given as follows: