(adsbygoogle = window.adsbygoogle || []).push({}); Realy Confused???

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.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Realy Confused?

**Physics Forums | Science Articles, Homework Help, Discussion**