When an object of lower density is surrounded by a fluid of higher density, the object rises to the top of the fluid. Clearly, a force is acting on the object, as it is accelerating upwards. I'm sure some physicist has given a name to this force, and there is also probably an equation for it, but I'm not sure what it is as my teacher did not teach it yet and I can get a more concise answer here than Google. So, what is the name and equation for this Density-Force? Thanks in advance.