How big your sphere of unknown matter is has nothing to do with it's mass determination.Corpuscles wrote:The reason there is a difference in the volume of the "water gram" and the "platinum gram" is its atomic mass number difference .....or its density!
You have accused Thornhill of circular logic , however you here demonstrate it yourself.
You are using known gravity, to weigh a substance or define the amount of substance that is arbitrarily attributed a gram "mass" value at specific temperature and pressure. Or compare weights of different objects to determine mass.
The subject is determination of gravity ! If mass is defined simply how much of a particular substance reacts to gravity then that is also circular logic in Newtons formula (I agree that this is how it is now done routinely without deeper thought) . Mathis is correctly pointing out this circular logic and directing the reader to what fundamental aspects of a particular type of matter determine it's mass..... and that is the fundamental chemistry of the substance.
Cheers
So my post didn't help you with the question of how to determine how much mass is in your 2 meter sphere, at all?!?!?!
I never referenced any density or gravity, and yet I gave you it's mass.
What does density have to do with the reference kilogram?
Chan, HELP! You're a lot more patient with this stuff!