Question

By what factor will the hydrostatic force on one of the vertical sides of a beaker decrease if the height of the liquid column is halved?

(a) ^1 ⁄ 2

(b) ^1 ⁄ 3

(c) ^1 ⁄ 4

(d) ^2 ⁄ 3

This question was addressed to me in an interview for job.

My query is from Hydrostatic Force on Plane Area topic in division Hydrostatic Forces on Surfaces of Fluid Mechanics

Answer 1

The correct option is (c) ^1 ⁄ 4

To elaborate: Hydrostatic force per unit width on a vertical side of a beaker = ^1 ⁄ 2 * ρgh^2, where ρ = density of the liquid and h= height of liquid column. Thus, if the liquid column is halved, the hydrostatic force on the vertical face will become one-fourth.