# Increasing Stability of Object in Water

1. May 29, 2012

### malek340

Basically i'm tying to work on a project that requires a heavy battery mounted on top of a foam floater. i believe that as long as the centre of gravity of the battery and the centre of buoyancy of the foam is close to each other, they will be stable in water or while floating on water. Correct me if i'm wrong. How to do exactly increase stability of them in water? By increasing the base area of float? or thickness of float?

2. May 29, 2012

### malek340

How do i*

3. May 29, 2012

### Infinitum

First up, you need to think about the center of gravity of the whole float-battery system. If the center of buoyancy and center of gravity are close to each other, the system will be in neutral equilibrium. To get a stable equilibrium, the center of buoyancy should preferably be above the center of gravity.

This can give you an idea : http://www.codecogs.com/reference/e...g_bodies/stability_and_metacentric_height.php

Based on the above, do you get an idea what you can do to increase the stability?

4. May 29, 2012

### malek340

So in short i have to put a a heavy object attached to the bottom of the floater. Does the weight of the object have to be heavier than the weight of the battery? So this floater (buoyancy force) have to to be able to carry up the weight of this object and the battery?

5. May 29, 2012

### Infinitum

Yes, but make sure that 'heavy object' keeps the floater still afloat. The weight of the object doesn't necessarily need to be heavier than the battery, infact, it being a bit less will be good too. It would be more appropriate if you know the densities and/or volumes of the materials involved.

6. May 29, 2012

### malek340

Thanks so much man! Appreciate ur time wasted on me man!

7. May 29, 2012

### malek340

Btw does increasing the base area and the thickness of the floater helps? Sorry for bothering you too much?

8. May 29, 2012

### Infinitum

Increasing the base area would make a difference, yes. Why don't you make a diagram and see how the center of gravity/buoyancy are effected by doing so?

Why do you call it wasted time?....

9. May 29, 2012

### malek340

Okay thanks man! Appreciate your time enlightening* me haha!