*sigh* I got my grade back for my test today...I missed these questions and I think *I* am right and my professor is WRONG. Q. When an object is partly or wholly immersed in a liquid, it is buoyed up: His answer: By a force equal to the weight of liquid displaced. My answer: By a force equal to its own weight. It's its own weight! Because that's the principle of flotation! If it is BUOYED UP, then it is FLOATING. Otherwise, it would be SINKING. If it is PARTLY IMMERSED, then it MUST be floating, and to be floating, the B.F. is equal to its weight. Am I right??? PLUS, you can float UNDER the water, I've seen logs doing so. FLOATING is FLOATING. The other question I got wrong was the one I tried to get answered last night...the one about "Place a 1-kg block of iron at 40 C in a kg of water at 20 C & final temp of the two becomes:" He says the "at or about 30 C" and I went with Less than 30 C. I think I'm right! Because of what someone else on the boards noted, the diff between the spec. heat capacities...you can't go mix and match different substances like that, can you? I'm depressed. I want to get some mental ammo and fight for those points.