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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 / A P stands for pressure, F stands for force, A stands for area. To calculate force multiply mass (kg) x the
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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 / A P stands for pressure, F stands for force, A stands for area To calculate force multiply mass (kg) x the acceleration 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 you creating pressure on air pockets in your head called 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 liquid 2. 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 p = Density of the liquid = mass of the liquid / the volume g = the acceleration of gravity, 10 N/kg 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 objects when submerged in a liquid http://www.youtube.com/watch?v=2afDLk-JzEY&feature=related
Buoyant Force Buoyant Force: the upward force exerted by a 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 http://www.youtube.com/watch?v=EIdph7ksnyY&feature=related • It makes no difference how deep an object • is under the surface of the fluid the • buoyant force is the same. http://www.youtube.com/watch?v=vJ36urazDu4
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 sink and 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 A floating object displaces a weight of fluid equal to its own weight. http://www.youtube.com/watch?v=VDSYXmvjg6M
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 the fluid and act in all directions. What does this mean in English? F/A = P = F/A Where F stands for force (N), A stands for area, P stands for pressure http://www.youtube.com/watch?v=epOwdGIDzlY http://www.youtube.com/watch?v=cBxOxwdDTPQ&feature=related