Liquids-They always take the shape of their container-They flow or you can pour them

Pressure

Pressure on an object is the force applied to a specific area

P = F / AP stands for pressure, F stands for force,

A stands for area

To calculate force multiply mass (kg) x theacceleration of gravity (10 m/s2)

Pressure Caused by Liquids

Have you ever swam down to the deep end of a pool and your ears started to hurt?

All the water above you is pushing down on youcreating pressure on air pockets in your headcalled sinuses

Does it matter how big the pool is or only how deep the pool is?

What Causes Pressure from Liquids?

Pressure from liquid is caused by three things;1. Gravity pulling down on the liquid2. The density of the liquid (Density = mass/volume)3. The depth of the liquid

How to Calculate Pressure from a Liquid

Pressure from a liquid= P = p x g x h

g = the acceleration of gravity, 10 N/kg

p = Density of the liquid = mass of the liquid / the volume

h = Depth = how far down from the top the object feeling pressure is

Buoyancy

Can you lift up a rock that is half your size?

- You can if the rock is in the water

Buoyancy: the apparent loss of weight of objectswhen submerged in a liquid

http://www.youtube.com/watch?v=2afDLk-JzEY&feature=related

Buoyant Force

Buoyant Force: the upward force exerted bya fluid on a submerged or immersed object

Archimedes’ Principle

• The buoyant force on an immersed object is equal to the weight of the fluid it displaces

-It makes no difference how deep an objectis under the surface of the fluid the buoyant force is the same.

http://www.youtube.com/watch?v=vJ36urazDu4

http://www.youtube.com/watch?v=EIdph7ksnyY&feature=related

Float or Sink?

What determines if an object will sink or float in water?

-It depends on the submerged objects buoyant force (pushing up) and its weight (pushing down).

If an object is more dense than water (1 g/ml) it will sinkand if it is less dense than water it will float.

If an object has the same density as the fluid surrounding it, it will not float or sink.

Floating

http://www.youtube.com/watch?v=VDSYXmvjg6M

A floating object displaces a weight of fluid equal to its own weight.

Pascal’s Principle (Hydraulics)Pascal’s Principle – changes in pressure at any

point in an enclosed fluid at rest are transmitted undiminished to all points in thefluid and act in all directions.

What does this mean in English?

F/A = P = F/AWhere F stands for force (N), A stands for area,

P stands for pressurehttp://www.youtube.com/watch?v=epOwdGIDzlY

http://www.youtube.com/watch?v=cBxOxwdDTPQ&feature=related