archimedes principles?

Question

help me plss...confuse

1 1 kg of iron and 1 kg of brass are suspended from different balance scales,each metal fully submerged in water.How do the scale readings compare? Express the answer as a function of the densities of the two materials.
2. a completely submerged chunk of metal sinks in water with an acceleration equal to 1/5 of g (where g = 9.8 m/s^2).Find the specific gravity of this metal.Ignore all the drag effects in th fluid.
3.A beach ball has a volume of 0.03 m^3.How much force would you have to exert to hold this beach completely under water?
4 A sinker was used to submerge a piece of cork beneath the water to determine the cork's specific gravity.Assuming the specific gravity is not known,why is it unnecessary to determine the specific gravity of the sinker?

BIG THANKS ! ! !please help me

Answer 1

1. This is a good question.

W-Fb=Ft
W= mg
Fb=V(p(H20))
Fb - Buoyant force
W- weight of brass
V- Volume of brass or iron
p(H20) - density of water

The difference will be Ft1-Ft2

and W1=W2=W
Ft1-Ft2=W1-Fb1 - W2+Fb2=
Ft1-Ft2=Fb2-Fb1
further and finally
Ft1-Ft2=(V2 -V1)p(H20)
where V1=m/p(brass) and V2=m/p(iron)


2. Something that forces the object to sink is a force difference between the weight of the object and the buoyant force of the liquid.
again Ft=W-Fb
Fb=W-Ft
Ft=(1/5)mg
Fb=mg-(1/5)mg
Fb=mg(1-1/5)=0.8mg

3. F=Fb=V p(H2O)
F= 0.03 m^3 (1000 kg/m^3) (9.81m/s^2)=294N

4. A specific gravity is the ratio of density relative to water. If you sunk the sinker and marked the volume and then sunk the cork then its only the volume of the cork you will measure.

Answer 2

The Archimedes thought states that the buoyant tension is comparable to the displaced fluid, which in incredibly uncomplicated words advise that the attempt mandatory to maintain something afloat would be the comparable by means of fact the attempt exerted to spread out the fluid or water quantity that it pushes out by using its presence. to maintain a dense metallic afloat in water, it may displace that mass of water which mass can exert adequate tension on the metallic physique. case in point, a stable metallic won't glide in water yet a water tight physique made out of metals will glide if the mass of metallic is so spread out and it takes up quantity to spread out its mass (ships have rooms and empty areas).