A person can lift 45 kg ( aprox 100lb). Using specific gravity as 10.17

Question

How many cubic meters of the metal could the person lift in

a) air ?

b) water ?

c) in water ?

Thanks

Answer 1

(a) Get the Volume by using V = Weight/(Density)= M g/(10.17*10^3 kg/m^3)
Ignore the buoyancy effect of air; it is negligible.
You get V = 0.043 m^3

(b) and (c) look the same to me. The effective density in water (with buoyancy force subtracted) is 9.17*10^3 kg/m^3. Repeat (a) with that instead of 10.17*10^3 in the denominator

Answer 2

Oh..

is actually

C)to find how many actual kg of metal is in this in air and in water?

mass of metal in water: .110kg
mass of metal in air: .122kg
mass of displaced water: .00706kg

Thanks

Answer 3

Since they tell you in the beginning that 45 kg can be lifted, I don't understand how you come up with 122 kg, or 0.122 kg, as the "mass of metal in air" that is "in this".

You must be omitting something

Answer 4

Oh..I didn't omit anything, I just added in the info of my recorded info from my lab...I wasn't sure if I'd need that.
I guess not then.

This question was a extra calculation question after the lab was done but I wasn't sure how to do this.

so the question and just the question with nothing extra added:

C)to find how many actual kg of metal is in this in air and in water?

sorry for the confusion =)