HIGH HEELS.

some problems caused by wearing high heels:

Stress fractures

cracks or breaks in the bones, more common as we age.

Twisted/sprained/broken ankles

from turning a foot while wearing a high-heeled shoe.

Pump Bump

enlargement of the back of the heel making it stick out and be red or swollen.

Joint pain

especially in the toes and on the balls of the feet, the joint can become chronically irritated and is worsened when heels are worn all the time.

Neuroma

tissue growth under the toes that results in extreme pain.

Back problems

may be related to wearing high heels and having poor postural alignment.

Blistering of the Feet

the shoe rubs the foot the wrong way, pushes two toes together, or otherwise squeezes the toes.

website:http://www.wisegeek.com/what-are-some-problems-caused-by-wearing-high-heels.htm

image website:http://www.google.com.sg/imghp?hl=en

how the moon affects ocean tides.

THE MOON AND TIDES.

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 TidesTides 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 TidesWhen 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.

do check out the website for more interesting facts! http://home.hiwaay.net/~krcool/Astro/moon/moontides/

difference between weight and mass.

Difference Between Mass and Weight

Students of physics often confuse mass and weight of an object and many also feel that there is no difference between the two, while the fact is that there is a lot of difference between the two.

Mass is the amount of matter present in a body and is an intrinsic property of the body. Mass of an object remains the same always at any place.

Weight on the other hand is the force which a given mass feels due to the gravity at its place. Weight is measured in units of Force like Newton (which is the SI unit of Force).

If your mass is 60 kgs then your weight is approximately 60 x 10 = 600 Newtons. This is because

Force = mass x acceleration (From Newton's second Law)

Thus, weight = mass x acceleration due to gravity

If you go to moon your mass remains same, i.e 60 kgs, but your weight becomes less by 1/6 amount, since moon's gravity is 1/6 that of earth.

Mass of a body is measured by balancing it equally with another known amount of mass. You keep known amount of masses like blocks of 1 kg, 2 kg etc on one side till both the sides balance and then add up the numbers on the known side of mass and thus calculate the unknown mass. This works because, when the masses are equal on both the sides of the balance the effect of gravity cancels out for both (i.e weight cancels out) and hence we can calculate the mass on one side of the balance if we know the mass on the other side of the balance.

Weight is measured using a scale which effectively measures the pull on the mass exerted by the gravity of the earth.

Table 1: Differences between Mass and Weight

	Mass	Weight
1.	Is always a constant at any place and time	Depends on gravity at the place
2.	Is measured in kilograms in SI unit	Is measured in Newtons (not in kilograms as one might think)
3.	Is measured using balance	Is measured using scales
4.	Can never be zero	Can also be zero
5.	Is an intrinsic property of a body and is independent of any external factor.	Depends on 1. Mass of the object which is attracting it 2. Force with which it is being attracted (which in turn depends on the distance between the two)

If an object is in freefall towards the attractor (like earth), even then it has weight, but it experiences weightlessness (like an astronaut in a spaceship around the earth) since it is obeying the force. Weight can be felt only when the body in question tends to oppose the force of gravity (like u and me sitting on the surface of the earth:-)

Remember that even though we are at rest due to the friction between our self and earth's surface, our acceleration is not zero, it is still 9.8 m/s² as the earth is constantly pulling us down towards its center. But we are resisting that pull and feel the force as weight.

website:http://www.hitxp.com/phy/cph/020902.htm

image fromhttp://www.google.com.sg/images?hl=en&gbv=2&tbs=isch:1&sa=3&q=weight+and+mass&btnG=Search+images

ICEBERGS

An iceberg is a large piece of ice from freshwater that has broken off from a snow-formed glacier orice shelf and is floating in open water. It may subsequently become frozen into pack ice. Alternatively, it may come to rest on the seabed in shallower water, causing ice scour (also known as ice gouging) or becoming an ice island.

Because the density of pure ice is about 920 kg/m³, and that of sea water about 1025 kg/m³, typically only one-tenth of the volume of an iceberg is above water. The shape of the underwater portion can be difficult to judge by looking at the portion above the surface. This has led to the expression "tip of the iceberg", for a problem or difficulty that is only a small manifestation of a larger problem.

Icebergs generally range from 1 to 75 metres (3–250 ft) above sea level and weigh 100,000 to 200 000 tons. The tallest known iceberg in the North Atlantic was 168 metres (550 ft) above sea level, making it the height of a 55-storey building. Despite their size, the icebergs of Newfoundland move an average of 17 kilometres a day (10 mi). These icebergs originate from the glaciers of westernGreenland, and may have an interior temperature of -15 to -20°C (5 to -4 °F).

Though usually confined by winds and currents to move close to the coast, the largest icebergs recorded have been calved, or broken off, from the Ross Ice Shelf of Antarctica. Iceberg B-15, photographed by satellite in 2000, measured 295 km long and 37 km wide (183-23 mi), with a surface area of 11,000 km² (4,250 mi²). The mass was estimated around three billion tonnes.

When an iceberg melts, it makes a fizzing sound called "Bergie Seltzer"". This sound is made when compressed air bubbles trapped in the iceberg pop. The bubbles come from air trapped in snow layers that later became glacial ice.

Ice campers who camp on top of flat or hollowed icebergs are known as icebergers.

SIZE

Names for various sizes of iceberg are not universal, but usually follow a similar pattern. The size classification in the table below is used by the International Ice Patrol:

Size Category	Height	Length
Growler	Less than 1 metre (3.3 ft)	Less than 5 metres (16 ft)
Bergy Bit	1–5 metres (3.3–16 ft)	5–15 metres (16–49 ft)
Small	5–15 metres (16–49 ft)	15–60 metres (49–200 ft)
Medium	15–45 metres (49–148 ft)	60–120 metres (200–390 ft)
Large	45–75 metres (148–246 ft)	120–200 metres (390–660 ft)
Very Large	Over 75 metres (246 ft)	Over 200 metres (660 ft)

source:http://en.wikipedia.org/wiki/Iceberg

source:http://images.google.com.sg/images?hl=en&q=icebergs&um=1&ie=UTF-8&ei=mSDDS7ujCc60rAe91um0CQ&sa=X&oi=image_result_group&ct=title&resnum=1&ved=0CBYQsAQwAA

difference between lime and lemon!

difference:

• A lime has denser flesh than a lemon which makes it heavier. Limes contain more acid than lemons, and are more sour (but lemons are small, green and more bitter before they mature and then turn yellow and more sweet when they mature. So what's the difference between a lime and an immature lemon?)
  

• When put into a glass or bowl of water, a lime will sink to the bottom, and a lemon will float on the top. Could the difference in density be due to a difference in sugar content or a difference in lipid (oil) content? Lipids are less dense than water. Lemons are known for their lemon oil. Cut a lemon and feel the oil on the surface. A small, dense, green, immature lemon floats in water!

source: http://wiki.answers.com/Q/What_is_the_difference_between_lime_and_lemon

source: http://images.google.com.sg/images?hl=en&source=hp&q=lemon+and+lime&gbv=2&aq=f&aqi=g3&aql=&oq=&gs_rfai=

cartesian diver(:

Experiment description

The Cartesian diver experiment is set up by placing a "diver"—a small, rigid tube, open at one end, such as aneyedropper—in a much larger container with some flexible component; for example, a two liter soft drink bottle. The larger container is filled with water, and must be airtight when closed. The "diver" is partially filled with a small amount of water, but contains enough air so that it is nearly neutrally buoyant, but still buoyant enough that it floats at the top while being almost completely submerged.

The "diving" occurs when the flexible part of the larger container is pressed inward, causing the "diver" to sink to the bottom until the pressure is released, when it floats again.

Explanation of the principles at work

Air in the diver makes it neutrally buoyant and therefore float at the water's surface. As a result of Pascal's Principle, when the pressure increases by squeezing the container, the least dense material, the air in the diver, is affected. Thus, the pressure on the water increases the pressure on the air bubble in the diver. The air compresses and reduces in volume, permitting more water to enter the diver. The diver now displaces a lesser weight of water than its own weight and becomes negatively buoyant (i.e. sinks), according to Archimedes’ principle. When the pressure on the container is released, the air expands again, increasing the weight of water displaced and the diver again becomes neutrally or positively buoyant and floats. If however, the buoyant force is equal to the compressed air force inside the diver, it will either float straight to the top or it will float in the middle of the container.

source: http://en.wikipedia.org/wiki/Cartesian_diver

INTERESTING FACTS: titanic!

i came across this really cool website go check it out for more information!

http://www.titanicstory.com/interest.htm

• In 1898 (14 years prior to the Titanic tragedy), Morgan Robertson wrote a novel called Futility. This fictitious novel was about the largest ship ever built hitting an iceberg in the Atlantic ocean on a cold April night. The fictional ship (named Titan) and the real ship Titanic were similar in design and their circumstances were remarkably alike. Both ships were labeled "unsinkable".
  

• RMS stands for Royal Mail Steamer. RMS, in formal terms, means "Royal Merchant Ship". However, the dual meaning was also "Royal Mail Steamer", because the Titanic carried mail under the auspices of His Majesty's postal authorities. At that time, all ships, military and civilian, that were under the British flag carried the distinction of "R.M.S." This, in effect, gave the ship the protection of the British Crown. An attack on an R.M.S. was considered an attack on the crown and an act of war.
  
• Two dogs were among the Titanic survivors.
  
• There were no cats on the Titanic. Cats were often brought on ships as a form of good luck. They also controlled rodents.
  
• The Titanic is about as long as the Empire State building is tall.
  
• The Tower Bridge, located in London England, is approximately the same length and height as the Titanic.
  
• Originally, the Titanic's design only included 3 funnels (smokestacks). The aftmost funnel (towards stern) was added to make the Titanic look more impressive-it gave the feeling of "power and grace". It only functioned as an air vent.

• No one ever claimed that the Titanic was "unsinkable". The quote, "practically unsinkable" was taken out of context. In 1911, Shipbuilder magazine published an article describing the construction of the Titanic. The article stated that when the watertight doors were closed, the ship would be "practically unsinkable".
  

• It was customary to break a bottle of champagne on the bow of a boat when launched. The Titanic launching did not include the traditional bottle-breaking.
  
• Many of the passengers were not originally suppose to be traveling on the Titanic. Due to a strike, coal was in short supply. This shortage threatened Titanic's maiden voyage and forced the White Star Line to cancel travel on the Oceanic and Adriatic and transfer their passengers and coal stocks to the Titanic.
  
• There were 13 couples on board celebrating their Honeymoons.
  
• Captain Smith was planning to retire after Titanic's maiden voyage.
  
• The Titanic had 4 elevators (3 in First class and 1 in Second class).
  
• At the time, Titanic's whistles were the largest ever made.
  
• Titanic's whistles could be heard from a distance of 11 miles.
  
• The Titanic carried 900 tons of baggage and freight.
  
• The Titanic used 14,000 gallons of drinking water every 24 hours.
  
• Coal consumption per day: 825 tons.
  
• Carried 20 lifeboats and 3560 life jackets. The life jackets were made of canvas and cork.
  
• More than 3 million rivets were used to build the Titanic.
  
• In a test done to determine stopping distance, the Titanic was accelerated to 20 knots and then the engines were reversed at full power. The distance required to stop the Titanic was about half a mile.
  
• The Titanic's radio call sign was: MGY.
  
• Port of Registry - Liverpool, England. Registry date: March 24, 1912.
  
• Official ship number: 131,428
  
• The number 3909 04 was NOT assigned to the Titanic as a hull number.

• The lookouts in the crow's nest did not have binoculars. Having binoculars might have prevented the Titanic tragedy.
  

• The time interval from first sighting of the iceberg to impact was a little over 30 seconds.
  
• The Titanic sank 2 hours and 40 minutes after hitting the iceberg.
  
• It probably took Titanic about 15 minutes to sink to her final resting place on the ocean floor. That means that Titanic sank at a rate of 10 miles per hour (or 16 km per hour).
  
• The Titanic hit the iceberg on the starboard (right) side of the bow. It has been speculated that the Titanic may have suffered only minor damage and minimal loss of life had it hit the iceberg head-on. It has also been suggested that the Titanic may have completely avoided colliding with the iceberg had the bridge not requested that the engines be reversed ("Full Astern"), prior to steering the ship to the left ("Hard-a-starboard"). This action would have decreased the forward momentum of the Titanic causing it to turn at a slower rate.
  
• July and August are the only two months the weather permits expeditions to the Titanic wreck site.

---

Strange, but True:

British spiritualist, William T. Stead, wrote a tale similar to Futility (mentioned at the top of the page). "How the Mail Steamer went down in the Mid Atlantic, by a survivor" appeared in the March, 1886 issue of Pall Mall Gazette. In this story, Stead tells of a large steamship that sinks after colliding with another ship. Many lives are lost due to lack of lifeboats. Stead wrote that, "This is exactly what might take place and what will take place, if the liners are sent to sea short of boats". Stead was travelling to the United States at the request of President Taft to address a peace conference at Carnegie Hall on April 20, 1912. Stead sat calmly in the library reading a book as the North Atlantic sea water came rushing in as the ship he was traveling on sank. That ship was the Titanic. Stead did not survive.

William T. Stead also authored the novel From the Old World to the New. In this book, he describes the sinking of a ship in the North Atlantic after striking an iceberg. To add to the irony, the captain of the ship which picked up the survivors, was Edward J. Smith -- the eventual captain of Titanic.

go to the website to continue reading!

why does an orange float with it's peel, but sinks when the peel is removed?

ANSWER: (http://wiki.answers.com/Q/Why_do_oranges_float)

Oranges float because with their peel on, their density is less than 1. The density of water is 1, and anything with a density less than 1 will float. However, if the peel is removed, the density will be more than 1, and the orange will sink.

The formula for finding density is:

Mass ÷ Volume=Density

orange image:http://images.google.com.sg/images?hl=en&q=orange%20peel&um=1&ie=UTF-8&sa=N&tab=wi

THE DEAD SEA.

the dead sea: (http://en.wikipedia.org/wiki/Dead_Sea)

The Dead Sea (Arabic: البَحْر المَيّت‎, al-Baḥr El-Mayyit, Hebrew: יָם הַ‏‏מֶּ‏‏לַ‏ח‎, Yām Ha-Melaḥ; "Dead Sea" , "Sea of Salt"), also called the Salt Sea, is a salt lake bordering Israel and the West Bankto the west, and Jordan to the east. Its surface and shores are 422 metres (1,385 ft) below sea level,^[2] the lowest elevation on the Earth's surface on dry land. The Dead Sea is 378 m (1,240 ft) deep, the deepest hypersaline lake in the world. It is also one of the world's saltiest bodies of water, with 33.7% salinity. Only Lake Assal (Djibouti), Garabogazköl and some hypersaline lakes of the McMurdo Dry Valleys in Antarctica (such as Don Juan Pond) have a higher salinity. It is 8.6 times more salty than the ocean.^[3] This salinity makes for a harsh environment where animals cannot flourish, hence its name. The Dead Sea is 67 kilometres (42 mi) long and 18 kilometres (11 mi) wide at its widest point. It lies in the Jordan Rift Valley, and its maintributary is the Jordan River.

The Dead Sea has attracted visitors from around the Mediterranean basin for thousands of years. Biblically, it was a place of refuge for King David. It was one of the world's first health resorts (forHerod the Great), and it has been the supplier of a wide variety of products, from balms forEgyptian mummification to potash for fertilizers. People also use the salt and the minerals from the Dead Sea to create cosmetics and herbal sachets.

dead sea image: http://images.google.com.sg/images?hl=en&q=the+dead+sea&um=1&ie=UTF-8&ei=h4O8S7e4OoW0rAfQs5ihBw&sa=X&oi=image_result_group&ct=title&resnum=1&ved=0CA8QsAQwAA

how would you measure the volume of a cork stopper?

answer:

Use a weight to hold down the cork. Find the volume of everything. Then subtract the volume of it's weight and water. You are left with the volume of the cork stopper.

(http://quizlet.com/385717/ips-quiz-bbq-flash-cards/)

(http://images.google.com.sg/images?hl=en&q=cork%20stopper&um=1&ie=UTF-8&sa=N&tab=wi)

MEASURING CYLINDERS

BURETTE (http://en.wikipedia.org/wiki/Burette)

A burette (also buret) is a vertical cylindrical piece of laboratory glassware with a volumetric graduation on its full length and a precision tap, or stopcock, on the bottom. It is used to dispense known amounts of a liquid reagent in experimentsfor which such precision is necessary, such as a titration experiment. Burettes are extremely accurate - a 50 cm³ burette has a tolerance of 0.1 cm³ (class B) or 0.06 cm³ (class A).

Burettes measure from the top since they are used to measure liquids dispensed out the bottom. The difference between starting and final volume is the amount dispensed

PIPETTE (http://en.wikipedia.org/wiki/Pipette)

A pipette (also called a pipet, pipettor or chemical dropper) is a laboratory instrument used to transport a measured volume of liquid.

Pipettes are commonly used in molecular biology as well as medical tests. Pipettes come in several designs for various purposes with differing levels of accuracy and precision, from single piece glass pipettes to more complex adjustable or electronic pipettes. Many pipettes types work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense.

Pipettes that dispense between 1 and 1000 μl are termed micropipettes, while macropipettes dispense a greater volume of liquid. Two types of micropipettes are generally used: air-displacement pipettes and positive-displacement pipettes. In particular, piston-driven air-displacement pipettes are micropipettes which dispense an adjustable volume of liquid from a disposable tip. The pipette body contains a plunger, which provides the suction to pull liquid into the tip when the piston is compressed and released. The maximum displacement of the plunger is set by a dial on the pipette body, allowing the delivery volume to be changed. Whereas for larger volumes cylindrical pipettes, such as volumetric or graduated pipettes are used and driven by a pipette aid.

pipette image: http://images.google.com.sg/images?hl=en&q=pipette&um=1&ie=UTF-8&sa=N&tab=wi