How can buoyant forces be measured?

Here's one easy way:-- Hang an object from a scale.  Write down its weight in air.-- Keep the object hanging from the scale, but let it down into water,or whatever fluid you're interested in.-- Read the scale again.  Write down its weight in the fluid.-- Dry everything off, clean up the lab, and go to your office with your notebook.-- In your notebook, turn to the page with that day's observations.Notice that the object's weight in air was greater than its weight in the fluid.-- Subtract the weight in fluid from the weight in air.The difference is the buoyant force on the object when it's in the fluid.