VIEWS: 4 PAGES: 27 POSTED ON: 10/11/2011
By: Erica Ambrogio What is needed to make the reaction take place? Fire is the visible effect of The products from the the process of combustion chemical reaction are – a special type of chemical completely different from reaction. It occurs between the starting material. oxygen in the air and some The fuel must be heated to sort of fuel. its ignition temperature for combustion to occur. The reaction will keep going as long as there is enough heat, fuel and oxygen How is it possible? There are certain chemicals Magnesium burns so hot it that, when accompanied splits the surrounding with their own source of water into hydrogen and oxygen, can burn oxygen, and burns with the underwater. oxygen. Magnesium and Sodium Makes it incredibly are elements that react difficult to put out. with water to create fire. Certain forms of Sodium actually EXPLODES upon contact with water: Underwater lake in Bikini Bottom? As unlikely as it sounds, there are a handful of underwater lakes and rivers boasting their own mini ecosystems. Brine Pools: Brine pools are large areas of brine on the ocean basin. These pools are bodies of water that have a salinity three to five times greater than the surrounding ocean. For deep-sea brine pools the source of the salt is the dissolution of large salt deposits through salt tectonics. Underwater Lake (Brine Pool) found at the bottom of the Gulf of Mexico Mr. Taylor has this clip This fast….? How does free-fall normally work? because free-falling objects are accelerating downwards at a rate of 9.8 m/s/s (a graph of the objects flight path would show acceleration) The dot diagram (next slide) shows the acceleration of a free-falling object. Shows the position of the object at constant time intervals The fact that the distance the object travels every interval of time is increasing is a sign that the ball is speeding up as it falls downward. When first jumping into a pool or lake or any type of water the body is accelerating just the same as in air (9.8 m/s) HOWEVER, the body will slow down rather than accelerating because of the resistance the water offers. Water does not flow as freely as other materials WHERES THE PROOF? As Spongebob and Patrick jump off the cliff, they will be accelerating for only about the first 5 seconds. After that, the resistance of the water will slow them down until eventually they are simply sinking in the water. What REAL free falling in water would be like: Fact or Fiction #4: Spongebob throwing marshmallows at Squidward FICTION! Newton’s Third Law of Motion An object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. “Objects keep doing what they’re doing.” INERTIA. So, What’s Wrong? • Based on this law we understand that the creators of Spongebob have got it wrong yet again. • Nothing was in the marshmallows path to stop it except for the water it began moving in. • However, even with the water slowing down the marshmallow, it would fall after losing its momentum. • Instead, the marshmallow changes direction on its own (also against the 1st law) and comes back to splatter on Squidward’s face. But doesn’t the marshmallow’s weight make a difference? • The tendency of an object to resist changes in motion changes with mass. Mass is the quantity that is solely dependent upon the inertia of an object. • The more inertia that an object has, the more mass that it has. A more massive object has a greater tendency to resist changes in its state of motion. • However, while the marshmallow would not have a lot of inertia it would continue to move regardless THE END.
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