Question #40068

1 Answer
Aug 18, 2016

Bouyant force will decrease as it makes the volume of the object

Explanation:

As Archimedes' principle explains:

The apparent weight of an object, W_"apparent"Wapparent, in a fluid equals to its weight, WW, minus the weight of the fluid which occupes its volume, BB

W_"apparent" = W - BWapparent=WB

where BB is buoyant force.

If you put a body on a fluid, it will occupe some volume of fluid. If this fluid has a density rhoρ, and the volume of the object is VV, the mass of fluid which will be occupied is:

m_"fluid" = rho Vmfluid=ρV

And the weight of this mass is right the buoyant force:

B = m_"fluid" cdot g = rho V gB=mfluidg=ρVg

As you see, buoyant force does not depend on the mass of the submerged body, but its volume. If you decrease its size, BB will reduce.