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## Homework Statement

This question is continued from a problem that I have already solved. This is what I know from the previous problem that will be helpful:

r= 0.20 m

roh of solid sphere= 850 kg/m^3

mass sphere= 3.94 x 10 ^-5 kg

I also have 2 apparent weights that I solved for when the tension in the system is

a. 150 N ----> Normal force (apparent weight) Fn = -1.49 x 10^2

b. 0 N -----> Fn = -3.86 x 10^-4 N

(Hopefully those are correct)

Now- the problem I came for help on:

A room is partially filled with water with a sphere in it and the sphere is on a scale. What percentage of the sphere must be immersed in the water in order to achieve the same apparent weights as above (a and b).

And- What percentage of the sphere must be immersed to achieve an apparent weight of zero?

## Homework Equations

% immersed = V immersed/ V total = roh obj/roh fluid

Bouyant force (Fb) = roh x V x g

Fn = mg + ma (a = O)

And from a full body diagram I have this:

Fn + Fb - mg = ma (whch is zero)

## The Attempt at a Solution

Well....I really am not sure what to do. One fact that I know and I think will help me is that if an object is say 90% underwater, then the roh of the object is 90% of the fluid....

I need a kick in the right direction please.