Question

A liquid is filled in a spherical container of radius r till a height h. At this position the liquid surface at the edges is also horizontal. The contact angle is

Answer 1

Hii dear,

◆ Answer- cosinv[(R-h)/R]

◆ Explanation-
[Refer to the figure]

Consider a sphere of radius R filled with fluid upto height h.

Let θ be the angle of contact of the fluid.
From the figure,
sin(π/4-θ) = (R-h)/R
cosθ = (R-h)/R

Taking inverse on both sides-
θ = cosinv[(R-h)/R]

Contact angle is cosinv[(R-h)/R].

Hope that is useful...