Two liquids A and B have θA and θB as contact angles in a capillary tube. If K = _A _B , K then identify the correct statement:

JEE Main 2025 Physics question

Two liquids A and B have θA and θB as contact angles in a capillary tube. If , K then identify the correct statement:

(1)K is negative, then liquid A has concave meniscus and liquid B has convex meniscus.Correct
(2)K is zero, then liquid A has convex meniscus and liquid B has concave meniscus.
(3)K is negative, then liquid A and B have convex meniscus.
(4)K is negative, then liquid A and liquid B have concave meniscus.

Answer: (1)

For concave meniscus θA<90°, for convex meniscus θB>90°, so cosθA/cosθB < 0

Question ID VK-002760