Buoyancy Definition and 405 Threads

I'm trying to do a lab for my physics class. It wants me to calculate the weight of the water displaced when I put a 500-g mass in a cup of water. I know the volume which is 59.0 ml. And I also know that the Buoyant force i s 0.56 N. I thought that the Buoyant force equals the volume of the...

I have a question that reads "A container of water is placed on a scale and the scale reads 120g. Now a 20 g piece of copper (specific gravity = 8.9) is suspended from a thread and lowered into the water but does not touch the bottom of the container. What will the scale now read round off to...

Let's say that I rig up a truck to a giant helium balloon, but I load up the back of the truck with enough stones so that the truck has reached a state of neutral buoyancy--its just floating in mid-air, not rising not falling, just there. Now let's say I take away a one-pound rock from the...

I have a homework question and it's taking me forever to figure it out. I can't seem to get the right answer. :frown:

Could someone please give me an accurate description of gravity, force, and buoyancy, and the relationships between them? F=ma, or Fg=G*((m1*m2)/(d*d)) ? Which is used in which situation? Does buoyancy affect weight, or merely counteract the effect of weight? Stuff like that would be...