Warmup 11/2 Monday

1. Warmup 11/2 Monday It is midnight, you are standing with your feet in the water on the beach facing the waves. Describe how the wind will be blowing?

2. Water Quality/chemistry Water-the universal solvent Dissolved Oxygen Turbidity Acid/base Nitrogen cycle (ammonia, nitrite, nitrate) Phosphates & Eutrophication Hard and Soft water Conductivity of water Alkalinity Water Physical properties Water pressure & Pascal's principle Scuba diving & dissolved gasses at pressure Surface Tension Heat capacity Buoyancy & Archimedes principle Density & the water density anomaly Bernoulli’s principle Water properties

3. Fluid = gases & liquids • Fluid = A fluid is a substance that easily and continually deforms (flows) under an applied force • Pressure of a fluid (gas and liquid) is the sum of all collisions of the particles on the

4. Wednesday, October 22, 2014 Aquatics Biology Finish Egg Lab Enter your Egg Lab data Make a graph of your data on the left hand side. Grab a Gateways textbook Open your INB to the next available page Title it Blood Cell Lab Being copying the questions for each station. • Pick up a copy of the Test review • Pick a group of 4 to work with • Complete Test Review • First group finished with the review earns 5pts on the test Friday

5. 1) Pascal’s Principle • Pressure applied to fluid in a closed container is equally transmitted to all parts of the fluid and the container. • Think toothpaste…

6. 1) Applications of Pascal’s Principle… • We use pascal’s principle a lot in things that need power… car jacks, car brakes, tractors & construction machines • Under water, the weight/pressure of the water is a “sqeeze” not a downward weight

7. 2) Effect of pressure on dissolved gas

8. Summary: There are several problems associated with scuba 1) Pressure is crushing even a small distance under the water (pascal’s principle) 2) Breathing air that is under pressure makes you a soda can! a) blood dissolves more air with pressure b) coming up fast can cause bubbles in your veins = painful… and deadly

9. 3) Surface tension • This bug will sink if it breaks the “surface tension • This bug & paperclip CANNOT do this on oil, alcohol or any other fluid!!! • This bug would not be able to do this in salt water either since the waters are all stuck to salt instead of each other.

10. 3) Surface tension is because of Hydrogen bonding

11. 3) Water has “surface tension” due to water molecules sticking together (hydrogen bonding)

12. 3) Summary Why can a bug that should sink, stay on top of the water? a) weak hydrogen bonds between water allow him to stand on the water b) the bug is less dense than water c) the covalent bonds are very strong d) water is very dense.

13. 4) Water has an extremely high heat capacity If you had 1gram Aluminum, 1gram of copper and 1gram of water and give each 1cal of heat. Aluminum will change about 5degrees Copper will change more than 10 degrees Water will only change 1degree

14. 4) Summary : Heat capacity of water Water … • takes in heat slowly, it does not change temperature fast • has more heat than most things – at the same temp • releases heat slowly too, so it can provide a constant source of heat at night

15. 4) Remember “convection” Heat makes things expand and rise Cold makes things contract and sink If one place it hotter,… what will happen to the air above it and thus the wind?

16. 4) The “Sea breeze”… that all coastal people know about.

17. question It is a sunny hot day around noon, you are standing with your feet in the water on the beach at Port Aransas facing the waves. The wind will most likely be blowing: • North • In your face • On your back • No way to know

18. question It is a sunny hot day around noon, you are standing with your feet in the water on the beach at Port Aransas facing the waves. The wind will most likely be blowing: • North • In your face • On your back • No way to know

19. 5) Buoyancy • Tankers are made of steel and weigh as much of 585,000tons!!! • They are 1500ft long, 225 ft wide… and extend >50ft into the water! • How do they float?

20. --- some things float and sink &--- why even things that sink feel lighter in water 5) The Buoyant Force is why…

21. 5) Archimedes principle

22. 5)Archimedes’ Principle Buoyant force = weight of fluid displaced

23. 5) Archimedes Example

24. 5) Archimedes principle: example

25. 5) Archimedes Example 2 lb fish, displacing 2.5lbs of water 2 lb fish, displacing 2lbs of water 2 lb fish, displacing 1.5lbs of water

26. Review “cartesian diver”Combo pascal & archimedes princ. Force on side equally transmitted up the tip Bubble is no “displacing” less water… less than it’s weight

27. Test question The force that holds floating objects up is the buoyant force, explained by…. a. Pascal’s principle b. Bernoulli's principle c. Archimedes's principle d. Density’s principle.

28. Test question The “cartesian diver” (dropper in a bottle) is an example of…. a. Pascal’s principle b. Bernoulli's principle c. Archimedes's principle d. both a and c.

29. Or: A ball weights 10 lbs, it will float if the same size ball of water weights… a. Less than 10 lbs b. more than 10 lbs c. 10 lbs is not that heavy , so it will always float d. 10 lbs is pretty heavy, so it will always sink

30. 6) Water’s density anomaly

31. Water Phases

32. 6) MOST things are denser as solids – lamp oil “ice” vs water “ice” • Most things continue to shrink as they “freeze” so the solid form is denser than the liquid form • H2O is the only compound we know of that expands when it freezes. • Solid water takes up more space than the same mass of liquid water… so due to Archimedes principle… it floats. • CAREFUL!!! – some of you have heard something I didn’t say! Liquid water still, in general, shrinks as it gets colder!!!!!!!!!!!!!!!!!!!

33. Water is unique!!!!! Ice has a density of 920 kg/m3

34. 6) Ever heard of a lake “turning over?” Ever heard of a lake “turning over?” 8 8 8 8

35. 0 = 32 8 = 39

36. Summary • Water is the only substance in your life whose solid form is LESS dense than it’s liquid form • This has huge impacts on the natural world!!!

37. 7) Bernoulli’s Principle The pressure of a fluid (gas or liquid) decreases as the fluid’s velocity increases.

38. 7) Bernoulli’s Principle The pressure of a fluid (gas or liquid) decreases as the fluid’s velocity increases.

39. 7) Does Bernoulli's principle apply to water too? • Of course, it applies to all fluids (gas & liquids) • Sharks especially use it to stay up… they normally sink if they stop moving.

40. 7) Bernoulli’ principle demos • Beach ball and leaf blower • Floating paper • Bubbles and cards • It’s harder to demonstrate with water…..

41. Reminder: know them by name We have talked about three principles that describe some physical properties of water Can you match them with their correct property: Bernoulli Archimedes Pascal • Buoyancy force is weight of displaced water • Fast flowing water has less pressure than slow water • Pressure is evenly distributed in all directions

42. Water pressure & Pascal's principle dissolved gasses at pressure Surface Tension Heat capacity Buoyancy & Archimedes principle Density & the water density anomaly Bernoulli’s principle Water properties