Buoyancy

What is buoyancy?

The ability to float.

Buoyancy

What is buoyancy?

The ability to float.

“Any body wholly or partially immersed in a fluid experiences an upthrust equal to, but opposite in sense to, the weight of the fluid displaced.”Archimedes Principle

Buoyancy

Forces in ActionBuoyancy: upward force on an object

Gravity: downward force on an object

Pressure: force all around an objectThe ability

to float.

Gravity

Buoyancy

Pressure Pressure

Buoyancy

Finding the Balance

The ability to float.

When there is a balance between the buoyant force and the force of gravity the object is said to be neutrally buoyant.

The key is to make an ROV that is as close to neutrally buoyant as possible, or the buoyant force should be slightly more than the

force of gravity (to prevent sinking).

BuoyancyTypes of Buoyancy

Positively Buoyant Neutrally Buoyant

Negatively Buoyant

Buoyancy

BallastDynamic (soft): system that changes the amount of water displace inside the ballast chamber.

Static: ballast chamber does not change. ROV is designed to be neutrally buoyant and motors move it up and down. The volume of air stays the same.

Center of Mass

Balance

Build an ROV Interactive:

http://www.mysticaquarium.org/fun-and-learning/games/302-build-an-rov

Frame Construction

Buoyancy and BalanceLet’s do an experiment!

Frame Construction

Buoyancy and BalanceLet’s make this

positively, neutrally, and negatively buoyant!

Let’s make this float!