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VIEWS: 4 PAGES: 27

									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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