Liquid exerts a force on objects immersed or floating in it. This force is equal to the weight of the liquid that is displaced by an object. This is also known as Archimedes’ principle. The unit for the buoyant force (like other forces) is the Newton (N).
Fb = ρgV = ρghA
Fb = buoyant force of a liquid acting on an object (N)
ρ = density of the liquid(kg/m3)
g = gravitational acceleration(9.80 m/s2)
V = volume of liquid displaced (m3 or liters, where 1 m3 = 1000 L)
h = height of water displaced by a floating object(m)
A = surface area of a floating object(m2)