WATER PROPERTIES

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Why do we want to explore the ocean?The Oceans are the number one driver of

weather and climateThey are also important for transportation

and foodTo learn about the organisms that live there

Almost every type of plant and animal known to science can be found in the ocean

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What is it like underwater?DarkDeepLots of pressureBigColdSalty

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Three Properties of Water• Density• Pressure• Buoyancy

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DensityHow much “stuff” is in a certain amount of

“space”

Mass is the amount of matter (stuff) in an object.

Volume is the amount of space an object takes up.

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Density ExampleA rock and a crumpled piece of paper are the

same size. They have the same Volume. The rock weighs more than the piece of

paper, it has greater Mass.

Which item has a greater Density?

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𝐷𝑒𝑛𝑠𝑖𝑡𝑦=𝑀𝑎𝑠𝑠𝑉𝑜𝑙𝑢𝑚𝑒

Density and States of Matter

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Density refers to how closely "packed" or "crowded" the material appears to be

Solid Liquid

Gas

http://www.cofc.edu/~martine/111LectWeek1_files/image008.jpg

PressureHow much force is applied to an area.Measured in Pascals (Pa), atmospheres

(ATM), or pounds per square inch (psi)There are many other units as well!

Water pressure is caused by the weight of water pressing down on what is beneath it.

The deeper you go, the more water is above you, the greater the pressure.

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𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒=𝐹𝑜𝑟𝑐𝑒𝐴𝑟𝑒𝑎

Water PressureWater and air are both fluids.

Water is more dense than air, so it “sinks.” In a bottle with half air and half water the

water stays at the bottom.

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Units of PressureAt sea level the pressure is equal to:

101,325 Pa14.7 psi1 ATM

Our bodies are used to this level of pressure, they exert the same amount of pressure back.

Underwater10 meters (33 feet) of water above you will

exert 1 ATM of pressure

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Water PressureThis Styrofoam cup

was sent to 1279 m and felt 1833 psi or 125 atmospheres of pressure

Why caused the cup to get smaller?

Has the density of the cup changed?

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http://iodp.tamu.edu/scienceops/gallery/exp311/week7/pages/exp311_107.html

High Pressure AdaptationsAnimals that live in the deep have adapted to a high pressure environment.No excess cavitiesSoft, pliable bones

www.pwssc.orghttp://ocean.nationalgeographic.com/ocean/photos/deep-sea-creatures/

BuoyancyThe ability of

something to float in a fluid (water, air, etc.)

Archimedes Principle: An object is buoyed up by a force equal to the weight of the fluid displaced by the object.

www.pwssc.org http://en.wikipedia.org/wiki/Image:Buoyancy.svg

States of BuoyancyPositive Buoyancy (float) The weight of the

object is less than the weight of the displaced water.

Negative Buoyancy (sink) The weight of the object is MORE than the weight of the displaced water.

Neutral Buoyancy (hover) The weight of the object is the SAME as the weight of the water displaced.

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