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I’m really confused. I have 2 questions and I was wondering if anybody can help me.

(1) First question: to Derive the equation Vi/Vtot = robject /rfluid .

The only other information given is a picture of an oval vertical shaped object that by looking at the picture is approximately 90% submerged in a fluid.

A: I know this problem is suppose to be worked out algebraically because no dimensions where given. I really having problem’s solving it. I know that Vi is the volume of fluid displaced by the object. I also have figured that to get the volume of the object is (4/3)(pi)abc, where a, b,c are the distances from the center to the edge on each axis. Also, I know that the density of the fluid is pgy. However I have no idea how to go about deriving this equation?

(2) Second question: What is the maximum thickness a steel sphere of radius R can have and still float on the surface of water?

Find the mass of such as sphere for

R = 2 m and R = 4 m.

This is what I have so far…….

Vol= 4/3 pi r^2

Vol= 4/3 pi 2m^2 -4/3 pi r(hollow center)^2= volume of the steel part

The density of steel: 7,800kg/m^3

Density of water: 1,000 kg/m^3

Density of air: 1.29 kg/m^3

mass of steel= 7800kg/m^3 * (4/3 pi 2m^2 -4/3 pi r(hollow center)^2)

density = mass/volume

100kg/m^3= mass of the steel/ volume

I am stumped here….I do not know if I have even gone about this problem the correct way. Thanks for your help.

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# Realy Confused?

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