Displacement GK 4th

What is Displacement?: 

What is Displacement? If the object is less dense than water (if it floats on water), it displaces a weight of water equal to the weight of the object. If the object sinks in water, it simply displaces a volume of water equal to the volume of the object. This is known as the Principle of Archimedes. Richard Barrans Jr., Ph.D.

Displacement Legend: 

Displacement Legend You are probably thinking of Archimedes' principle. Archimedes was a Greek philosopher. The story goes that the king of the day wanted a new crown made entirely of gold. After the goldsmith made it, the king was suspicious that the goldsmith made it of iron and coated it with gold. The king did not want to destroy the crown if in fact it were gold, so he asked Archimedes to figure out if it was pure gold or not without destroying the crown. Archimedes pondered this day in and day out until one day while getting into his bath he discovered the principle that bears his name. The tub was full to the rim, and when he sat down in it, he noticed that the more he sank himself into the water, the more water that spilled over the side of the tub. He was supposedly so happy to make this discovery that he ran out into the streets shouting "I found it!" What he discovered is that the amount of water displaced by an object depends on the mass of that object (not the weight). If he knew the mass of that object, and the volume of fluid it displaces, he could determine its density. Since the densities of iron and gold are different, he did a test. He determined the density of the crown and compared it to the density of pure gold to see if they were the same. Legend says they were not the same, so the king was tricked.

Information about Displacement: 

Information about Displacement Eric Tolman Computer Scientist says: This is called the law of bouyancy, discovered by Archimedes, and basically says: any material or object immersed in a fluid will tend to rise through the fluid if the fluid density is greater than the material density. The force associated with buoyancy is the difference between the weight of the displaced fluid and the weight of the immersed material.

Uses of Displacement: 

Uses of Displacement Weighing Trout by Water Displacement Displacement loading uses the fact that 1.02 pounds of trout displace 1.0 pound of water, regardless of fish size. Usually a transportation tank is filled with water to a specific mark on the inside of the tank. The fish are loaded until the water reaches a second mark.

Conserving Water "When the well is dry, we know the worth of water".- Benjamin Franklin, Poor Richard's Almanac : 

Conserving Water "When the well is dry, we know the worth of water". - Benjamin Franklin, Poor Richard's Almanac A water displacement apparatus can be used in older toilets. Fill a plastic bottle with water, add something to the inside (such as pebbles) for weight, and place it in the bottom of the tank where it will not interfere with the flushing mechanism. DO NOT use this method in the newer low—water use models.

Use in Water Vessels: 

Use in Water Vessels Pontoons In the olden days, before there were engines, all boats were displacement boats. A displacement  boat is designed to glide through the water smoothly with a minimum of power (like a canoe with oars or a sailboat under sail). Generally, these boats are very stable and ride smoothly. Larger displacement vessels were also designed to efficiently and safely carry lots of cargo or people.

Slide7: 

You might think something like a ship is more dense than water, after all, it is made of metal which is certainly more dense than water, but, the ship is filled with air, which is much less dense than water, and makes up the difference. That is why, when a ship gets a hole in it, it sinks. The water pushes out all the air and makes the total density of the ship greater. When the water, metal, and air inside the ship become more dense than the water outside the ship, the ship will sink. and Note that this will not work for a porous object, which will absorb some of the liquid!

Link Page: 

Link Page http://www.newton.dep.anl.gov/askasci/phy99/phy99x34.htm Graphics from MS Office