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TO SINK OR TO FLOAT. Grade Eight Science. Fill in the Missing Answers (8K). On Your Own (8k). Bladders and Ballasts. Bladder? Ballast?. Swim Bladder. Fish control their depth in water by using their swim bladder.
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TO SINK OR TO FLOAT Grade Eight Science
Bladders and Ballasts • Bladder? • Ballast?
Swim Bladder • Fish control their depth in water by using their swim bladder. • To increase the amount of air inside their bladder they can gulp in air at the surface or release dissolved gases (air) from their blood. • Dissolved Gases? What? Examples? • Increased air?
Swim Bladder Cont’d • To decrease the amount of water the fish simply releases air or gases into the water. • Releasing air in swim bladder results in?
Rockweed and Seaweed • Swim bladders? • Why or why not?
Human Adaptations • Overall density is very similar to that of water, therefore a “relaxed swimmer with filled lungs is positively buoyant.” • Wet suit = + Buoyancy • Weights = - Buoyancy • Compensator vest = increases and decreases and allows for neutral buoyancy • By increasing or decreasing air levels, what important property are we changing.
Similarities • In what ways are fish bladders and buoyancy compensator vests similar?
Ballasts • Ballast is any material on ships, submarines, hot air balloons, or dirigibles (air ships); dir-i-juh-buhl that acts as weight and alters the buoyancy. • Examples? • Sand, water • Ballast Tanks • Specifically designed tanks that hold the ballast
Ballast Tanks • Ballast used in submarines and ships is water. • Ships generally dump most or all of the water when they pick up cargo. • A ship that floats lower in the water is much more stable and thus the perfect amount of ballast is necessary.
Ballast Tanks Cont’d • Submarines use ballast to control the depth at which they travel. http://www.worsleyschool.net/science/files/sub/marines.html
Unrelated But Amazing • http://www.youtube.com/watch?v=g4RQXkI3B8w&feature=related&safety_mode=true&persist_safety_mode=1&safe=active
Boat Wrap Up • Two wishes • How could you have improved your boat? • What should you have done differently? • What feature should I have changed • Features: Size, thickness, volume • and a star? • What was the best feature of my boat? • How did it help? • Three small paragraphs