ARCHIMEDES´PRINCIPLE

Science

The question of why some objects sink in fluids while others float can be answered using the law of buoyancy.

This law is known as Archimedes' principle, after the ancient Greek scientist who discovered it. 

Archimedes Principle

It can be expressed as ‘Any object, wholly or partially immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.

According to a tale, Archimedes discovered this law while taking a bath. After making this discovery, he is said to have leapt out of his bathtub and ran through the streets of Syracuse naked shouting "Eureka!".

If the weight of the water displaced is less than the weight of the object, the object will sink

An object will float, with the weight of the water displaced equal to the weight of the object.

It states that "any body partially or completely submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body.

" The weight of an object acts downward, and the buoyant force provided by the displaced fluid acts upward. If these two forces are equal, the object floats.

If you’ve ever tried to push a beach ball underwater, you’ve felt this principle in action.

As you push the ball down, it pushes back up. In fact, a big beach ball can be tough to hold underwater. As a physicist in a bathing suit, you may wonder, “What’s happening here?”

http://www.youtube.com/watch?v=y0SnFCs9z1g THEORY

http://www.youtube.com/watch?v=Mmc1whyS78k HISTORY

http://www.youtube.com/watch?v=s5eIRjmor1w EXPERIMENT

QUESTIONS???

Who discover the principle? How? Explain it, use 3 examples, with graphics.

What´s the opposing force to gravity? Is equal if you talk about a ship with

cargo or empty? Yes /no? why? ______, _____ and ____work together

to determine what floats your boat, or sinks your ship