The word "tides" is a generic term used to define the alternating rise and fall in sea level with respect to the land, produced by the gravitational attraction of the moon and the sun. To a much smaller extent, tides also occur in large lakes, the atmosphere, and within the solid crust of the earth, acted upon by these same gravitational forces of the moon and sun.
What are Lunar Tides
Tides are created because the Earth and the moon are attracted to each other, just like magnets are attracted to each other. The moon tries to pull at anything on the Earth to bring it closer. But, the Earth is able to hold onto everything except the water. Since the water is always moving, the Earth cannot hold onto it, and the moon is able to pull at it. Each day, there are two high tides and two low tides. The ocean is constantly moving from high tide to low tide, and then back to high tide. There is about 12 hours and 25 minutes between the two high tides.
Tides are the periodic rise and falling of large bodies of water. Winds and currents move the surface water causing waves. The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon. Another bulge occurs on the opposite side, since the Earth is also being pulled toward the moon (and away from the water on the far side). Ocean levels fluctuate daily as the sun, moon and earth interact. As the moon travels around the earth and as they, together, travel around the sun, the combined gravitational forces cause the world's oceans to rise and fall. Since the earth is rotating while this is happening, two tides occur each day.
What are the different types of Tides
When the sun and moon are aligned, there are exceptionally strong gravitational forces, causing very high and very low tides which are called spring tides, though they have nothing to do with the season. When the sun and moon are not aligned, the gravitational forces cancel each other out, and the tides are not as dramatically high and low. These are called neap tides.
Spring Tides
When the moon is full or new, the gravitational pull of the moon and sun are combined. At these times, the high tides are very high and the low tides are very low. This is known as a spring high tide. Spring tides are especially strong tides (they do not have anything to do with the season Spring). They occur when the Earth, the Sun, and the Moon are in a line. The gravitational forces of the Moon and the Sun both contribute to the tides. Spring tides occur during the full moon and the new moon.
Neap Tides
During the moon's quarter phases the sun and moon work at right angles, causing the bulges to cancel each other. The result is a smaller difference between high and low tides and is known as a neap tide. Neap tides are especially weak tides. They occur when the gravitational forces of the Moon and the Sun are perpendicular to one another (with respect to the Earth). Neap tides occur during quarter moons.
The Proxigean Spring Tide is a rare, unusually high tide. This very high tide occurs when the moon is both unusually close to the Earth (at its closest perigee, called the proxigee) and in the New Moon phase (when the Moon is between the Sun and the Earth). The proxigean spring tide occurs at most once every 1.5 years.
Taken From: http://home.hiwaay.net/~krcool/Astro/moon/moontides/
Apr 17, 2010
Cartesian Diver.
This is the simplest explanation I could find:
When pressure is applied to the bottle of water, the liqiud in the bottle will cause the air in the "Diver" to be compressed. When it is compressed, the volume of the air in the "Diver" decreases. Therefore, the density also increases. When the density increases, the "Diver" would sink to the bottom of the bottle.
When we let go of the bottle, there would be less pressure and the air in the "Diver" would go back to its original volume and its density would decrease and it would float.
Taken From: http://www.youtube.com/watch?v=ySISRfNkDiE&feature=related
When pressure is applied to the bottle of water, the liqiud in the bottle will cause the air in the "Diver" to be compressed. When it is compressed, the volume of the air in the "Diver" decreases. Therefore, the density also increases. When the density increases, the "Diver" would sink to the bottom of the bottle.
When we let go of the bottle, there would be less pressure and the air in the "Diver" would go back to its original volume and its density would decrease and it would float.
Taken From: http://www.youtube.com/watch?v=ySISRfNkDiE&feature=related
Apr 11, 2010
Lava Lamps
Lava Lamps are novelty items normally used for decorations. But What are the blobs floating up and down the lamp?? Those blobs are wax.
The lamp contains a halogen lamp that heats a bottle containing water and the wax(usually transparent translucent or opaque) up. Wax is slightly denser than water at room temperature. However, when its heated up, it becomes less dense. This is because wax expends more than water when both are heated. When heated the wax becomes more fluid and its specific gravity increases and the blobs of wax ascend to the top of the device where they cool and then descend. There is a metallic coil of wire at the bottom of the bottle acts as a surface tension to recombine the cooled blobs of wax.
Hazards of the lava lamp:
In 2004, Phillip Quinn, was killed in an attept to heat a lava lamp on his kitchen stove while observing it a few feet away. The heat fro the fire built up pressure in the lamp and it exploded. The glass broke and it was strong enough to pierce through his chest, heart and causing fatal injuries. The circumstances were proved and comfirmed in a popular science series, Mythbusters. The show also noted that even if the glass did not was not iwth lethal velocity during such an attempt, the hot wax would be enough to cause severe burns. They noted that no one should ever heat a lava lamp on a kitchen stove.
Some Videos:(PART 1) http://www.youtube.com/watch?v=W7_dVUx5lZU
(PART 2) http://www.youtube.com/watch?v=azHzE-5cO3A&feature=related
The lamp contains a halogen lamp that heats a bottle containing water and the wax(usually transparent translucent or opaque) up. Wax is slightly denser than water at room temperature. However, when its heated up, it becomes less dense. This is because wax expends more than water when both are heated. When heated the wax becomes more fluid and its specific gravity increases and the blobs of wax ascend to the top of the device where they cool and then descend. There is a metallic coil of wire at the bottom of the bottle acts as a surface tension to recombine the cooled blobs of wax.
Hazards of the lava lamp:
In 2004, Phillip Quinn, was killed in an attept to heat a lava lamp on his kitchen stove while observing it a few feet away. The heat fro the fire built up pressure in the lamp and it exploded. The glass broke and it was strong enough to pierce through his chest, heart and causing fatal injuries. The circumstances were proved and comfirmed in a popular science series, Mythbusters. The show also noted that even if the glass did not was not iwth lethal velocity during such an attempt, the hot wax would be enough to cause severe burns. They noted that no one should ever heat a lava lamp on a kitchen stove.
Some Videos:(PART 1) http://www.youtube.com/watch?v=W7_dVUx5lZU
(PART 2) http://www.youtube.com/watch?v=azHzE-5cO3A&feature=related
Apr 6, 2010
What Is Density??????????
Density is the physical property of matter. It is defined as its mass per unit volume. The symbol is a 'P', greek for Rho.
The History of Density:
In a well-known tale, Archimedes was given the task of determining whether King Hiero's goldsmith was embezzling gold during the manufacture of a wreath dedicated to the gods and replacing it with another, cheaper alloy.
Archimedes knew that the irregularly shaped wreath could be crushed into a cube whose volume could be calculated easily and compared with the mass; but the king did not approve of this.
Baffled, Archimedes took a relaxing immersion bath and observed from the rise of the warm water upon entering that he could calculate the volume of the gold crown through the displacement of the water. Allegedly, upon this discovery, he went running naked through the streets shouting, "Eureka! Eureka!" . As a result, the term "eureka" entered common parlance and is used today to indicate a moment of enlightenment.
The story first appeared in written form in Vitruvius' books of architecture, two centuries after it supposedly took place. Some scholars have doubted the accuracy of this tale, saying among other things that the method would have required precise measurements that would have been difficult to make at the time.
Information taken from:
http://en.wikipedia.org/wiki/Density
The History of Density:
In a well-known tale, Archimedes was given the task of determining whether King Hiero's goldsmith was embezzling gold during the manufacture of a wreath dedicated to the gods and replacing it with another, cheaper alloy.
Archimedes knew that the irregularly shaped wreath could be crushed into a cube whose volume could be calculated easily and compared with the mass; but the king did not approve of this.
Baffled, Archimedes took a relaxing immersion bath and observed from the rise of the warm water upon entering that he could calculate the volume of the gold crown through the displacement of the water. Allegedly, upon this discovery, he went running naked through the streets shouting, "Eureka! Eureka!" . As a result, the term "eureka" entered common parlance and is used today to indicate a moment of enlightenment.
The story first appeared in written form in Vitruvius' books of architecture, two centuries after it supposedly took place. Some scholars have doubted the accuracy of this tale, saying among other things that the method would have required precise measurements that would have been difficult to make at the time.
Information taken from:
http://en.wikipedia.org/wiki/Density
Face Blotters
Most women would have at least a pack of these in their handbags or in their cosmetic pouch. Many people like seeing the oily stains on the paper, like me :D, tissue paper works in just the same way. Anyway, if you squeeze the oil out, your skin will get drier and it just results in more facial oil. These face blotters also make no difference in helping to control the facial oil. Another thing to avoid is powedered facial blotters as the powder would just cover up thepores in your face and will potentially cause more skin problems in the future.
Hope theses tips have helped you!!!! :D
Info taken from:http://www.vivawoman.net
Hope theses tips have helped you!!!! :D
Info taken from:http://www.vivawoman.net
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