Why don't birds die when they perch on high-voltage power lines?

It’s not unusual to see lines of birds perched on power lines. But did you ever wonder why birds aren’t electrocuted by the currents that flow through these high-voltage wires?

You might think it’s because the wires are insulated, but they’re actually not insulated at all — that’s why downed power lines are so dangerous. No, the only reason why birds on power lines usually aren’t electrocuted is because the wire is the only thing they’re touching!

Why No Zap?

Like all energy, electricity seeks equilibrium, or balance. That means electricity will flow from high-energy areas to areas of less energy, always using the path of least resistance. So if the bird has one foot on our original wire, and the other foot on, for example, the ground or on a different wire with less voltage, the bird would be electrocuted. The electricity would pass through the bird on its way from the high-voltage line to the lower-voltage line or the ground.

But as long as both of the bird’s feet are on the same wire (or wires of the same voltage), the bird is safe. The current doesn’t have anywhere else to go, so the electricity won’t pass through the bird–it stays on the path of least resistance, the wire.

Don’t Try This At Home!

This would work for humans, too–if you were to hang suspended from one of these wires, you wouldn’t be electrocuted, as long as you didn’t get too close to anything else, like a telephone pole or the ground. But don’t try this experiment at home! If you want proof, just look up at the birds on the wires!

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Why do some trees lose their leaves for winter?

Deciduous trees lose their leaves every winter, rather than maintaining green foliage throughout the year like evergreens do. Often, the trees provide a radiant show of fall color before they lose their leaves, and in some regions, this fall color is a vacation attraction that visitors from all over enjoy. There are a number of reasons for leaf loss, but essentially, it happens to conserve energy over the winter and prevent damage to the tree. In the spring, the tree puts out new leaves so that the process can begin anew.

Many deciduous trees are found in regions which have cold, dark, harsh winters. Trees lose their leaves to protect themselves during the winter months, as the cold dry winds in these regions will readily strip moisture from the trees through the leaves, which have a large surface area. By losing their leaves, trees can conserve their moisture in the trunk and branches, rather than drying out and dying. In addition, the leaf loss puts the tree into a state of dormancy, and greatly reduces the amount of energy that the tree needs to stay alive.

During the spring and summer, leaves photosynthesize the plentiful sunlight that falls on them, producing chlorophyll, which turns them green. The photosynthesis provides energy for the tree, and the tree feeds the leaves with nutrients it takes up from the ground to keep them healthy. The bright yellows, oranges, and reds that make fall color distinctive are actually already there all the time, but the chlorophyll masks them. As the days get shorter, the trees have less sunlight to work with, and the efficiency of the leaves starts to decrease. The leaves fall because they become a draw on the energy of the tree, as the tree would otherwise have to feed the leaves through the winter.

As the nights get longer, trees make preparations to lose their leaves, starting with the secretion of chemicals to cut the leaf off from the rest of the tree. As the leaves stop producing chlorophyll, they start to change color. Ultimately, trees lose their leaves once the chemicals they secrete have effectively cut the leaves off from the parent branch. These chemicals, primarily ethylene and abscisic acid, make the leaves fall by severing the link between the leaf and the tree. The leaves fall to the ground, providing a layer of protective mulch to insulate the roots, and the tree conserves its energy for the next year and a new growing season.

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Why do bats hang upside down?

This is a little like asking, "Why do people walk with their legs?" People could walk on their arms instead, and some people (acrobats for example) actually do it sometimes. But our legs are a lot stronger than our arms, and the whole human body is set up for walking with the legs. Walking with the legs is easy and comfortable and natural. So we usually walk with our legs rather than our arms.

It is the same for bats. A bat's body is set up to hang upside down. In fact, if you look at a bat's legs, they are set up so that, without doing anything, they naturally cling when the bat is upside down. The weight of the bat pulls on tendons that hold the feet closed. So bats hang upside down because it is easy and comfortable and natural for the bat.

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Why don't microwave ovens heat food containers?

Home materials are fine in the microwave and some aren’t (see below). And then there’s plastic. You’ll find experts who say no plastic containers should be used in the microwave—ever. “The material contains chemicals that may leach into food when it’s heated,” says Olga Naidenko, Ph.D., a scientist with the Environmental Working Group, a health-research organization. However, the U.S. Food and Drug Administration (FDA) has deemed that plastics labeled “microwave-safe” are suitable for microwave use. “No studies have shown short- or long-term health consequences from heating microwave-safe plastics,” says Michael Herndon, an FDA spokesman. The bottom line? Right now, there isn’t one. If you choose to use plastics, stick with those labeled “microwave-safe” (but don’t allow plastic wrap to touch your food during heating). If you’re wary, use glass or ceramic dishes marked “heatproof” or “microwave-safe.”

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Why are Pulitzer prize winners always American?

In the latter years of the 19th century, Joseph Pulitzer stood out as the very embodiment of American journalism. Hungarian-born, an intense indomitable figure, Pulitzer was the most skillful of newspaper publishers, a passionate crusader against dishonest government, a fierce, hawk-like competitor who did not shrink from sensationalism in circulation struggles, and a visionary who richly endowed his profession.

His innovative New York World and St. Louis Post-Dispatch reshaped newspaper journalism. Pulitzer was the first to call for the training of journalists at the university level in a school of journalism. And certainly, the lasting influence of the Pulitzer Prizes on journalism, literature, music, and drama is to be attributed to his visionary acumen.

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Why do we newlyweds take a honeymoon?

Wedding season is almost upon us, which means that many happy couples are eagerly planning their much-anticipated honeymoons. Whether you are headed to Punta Cana or San Diego, the excitement and joy you feel will likely make any location a dream come true. Yet there are some things to keep in mind as you pack up your sunscreen and bikini.

Here are the top five tips that can help ensure you have the best honeymoon ever:

Enjoy the art of doing nothing. After months of wedding planning, you likely need some major R & R. However, many honeymooners over-schedule themselves and get caught up in vacation anxiety as they try to pack in as much sightseeing as possible. Still, don’t get so caught up in “enjoying” yourselves that you can’t see the forest for the trees (or the beach for the sand, as the case might be!) It’s okay if you sleep in and you miss the breakfast buffet or if you rather spend the day in bed with your partner instead of in a long queue at the local tourist trap. As long as you and your partner are having fun, it doesn’t matter if you never see more the inside of your hotel room.

Remember why you came. Historically, honeymoons were a time for a young couple to escape the hubbub of their everyday lives, to bond with each other, and to become intimate with one another for the first time. Of course, in this day and age, most couples already have been intimate with one another before their wedding night (and some might already even live together). But this doesn’t mean that your honeymoon still shouldn’t be about bonding and intimacy. It’s more than just a regular vacation. It’s about celebrating the beginning of your lifetime journey as a couple and about creating memories that you will cherish for the rest of your lives. When you consider that, it’s easy to realize that getting a tan is just a bonus.

Break sexual boundaries. Even if and your partner have already been intimate, your honeymoon can still be a time of sexual exploration and discovery. From racy lingerie to erotica to sex toys, there are so many ways you can spice up your connection, but most importantly, make it your goal to bring to life at least one of your major sexual fantasies. For example, have you always wanted to sex in the ocean, or have you often fantasized with your partner about joining the Mile High Club? Make it your honeymoon goal to do at least sexual act that gets your heart racing and your adrenaline pumping, and then remember to keep that spirit alive after the honeymoon as well!

Have realistic expectations. It’s natural to fantasize about your big day and have high hopes when you board off the plane. However, be prepared for a few things to go wrong (from lost luggage to incorrect hotel reservations, traveling rarely comes without complications). Instead of fighting the chaos, embrace it. For example, if an unexpected rain storm hits the beach, don’t mope angrily in your hotel room. Instead, you and your partner can relax under the safety of a cabana and enjoy a few island drinks as you wait out the storm and laugh over your wedding day memories. The bottom line is that if you set off on your honeymoon with a spirit of adventure and a determination to have fun no matter what, then that’s exactly what you will do.

Be prepared for post-wedding blues.  Once the wedding gifts have been unwrapped and the revelers have all gone home, it’s natural to feel a twinge of post-wedding blues, even if you are headed to a sunny beach. Most couples spend months or even years planning their big day, so when it is all over, it can be hard to let go of all that anticipation. Now that there are no more invitations to design or cakes to taste, it’s natural to feel a bit melancholy, no matter how perfect the wedding day was. But, remember, the wedding day is just one of innumerable happy memories you will build with your new spouse, not to mention, you can relive those memories as you look over the beautiful photographs of the day.

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Why is April the First a day for fools?

The origins of April Fools' Day are uncertain, but without doubt they are linked to a time when the year was deemed to begin in late March or early April. In many cultures, the New Year is a time for pranks and merriment.

April Fools' Day, sometimes called All Fools' Day, is one of the most light-hearted days of the year. Its origins are uncertain. Some see it as a celebration related to the turn of the seasons, while others believe it stems from the adoption of a new calendar.

New Year's Day Moves

Ancient cultures, including those of the Romans and Hindus, celebrated New Year's Day on or around April 1. It closely follows the vernal equinox (March 20th or March 21st.) In medieval times, much of Europe celebrated March 25, the Feast of Annunciation, as the beginning of the new year.

In 1582, Pope Gregory XIII ordered a new calendar (the Gregorian Calendar) to replace the old Julian Calendar. The new calendar called for New Year's Day to be celebrated Jan. 1. That year, France adopted the reformed calendar and shifted New Year's day to Jan. 1. According to a popular explanation, many people either refused to accept the new date, or did not learn about it, and continued to celebrate New Year's Day on April 1. Other people began to make fun of these traditionalists, sending them on "fool's errands" or trying to trick them into believing something false. Eventually, the practice spread throughout Europe.

Problems With This Explanation

There are at least two difficulties with this explanation. The first is that it doesn't fully account for the spread of April Fools' Day to other European countries. The Gregorian calendar was not adopted by England until 1752, for example, but April Fools' Day was already well established there by that point. The second is that we have no direct historical evidence for this explanation, only conjecture, and that conjecture appears to have been made more recently.

Constantine and Kugel

Another explanation of the origins of April Fools' Day was provided by Joseph Boskin, a professor of history at Boston University. He explained that the practice began during the reign of Constantine, when a group of court jesters and fools told the Roman emperor that they could do a better job of running the empire. Constantine, amused, allowed a jester named Kugel to be king for one day. Kugel passed an edict calling for absurdity on that day, and the custom became an annual event.

"In a way," explained Prof. Boskin, "it was a very serious day. In those times fools were really wise men. It was the role of jesters to put things in perspective with humor."

This explanation was brought to the public's attention in an Associated Press article printed by many newspapers in 1983. There was only one catch: Boskin made the whole thing up. It took a couple of weeks for the AP to realize that they'd been victims of an April Fools' joke themselves.

Spring Fever

It is worth noting that many different cultures have had days of foolishness around the start of April, give or take a couple of weeks. The Romans had a festival named Hilaria on March 25, rejoicing in the resurrection of Attis. The Hindu calendar has Holi, and the Jewish calendar has Purim. Perhaps there's something about the time of year, with its turn from winter to spring, that lends itself to lighthearted celebrations.

Observances Around the World

April Fools' Day is observed throughout the Western world. Practices include sending someone on a "fool's errand," looking for things that don't exist; playing pranks; and trying to get people to believe ridiculous things.

The French call April 1 Poisson d'Avril, or "April Fish." French children sometimes tape a picture of a fish on the back of their schoolmates, crying "Poisson d'Avril" when the prank is discovered.

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Why do we eat three meals a day?

Human body needs food to fuel the processes that keep it alive and warm and provide the energy to move and work. Eating three meals a day seems sensible, but is it healthy? When you want to feel and look your best, it's hard to ignore the conflicting claims that grazing all day or skipping meals is the best way to reach your goals. This is one case where it may be healthiest to stick with tradition.

Meal Frequency and Weight

The average American eats 3.12 meals a day, and a three-meals-a-day pattern is the norm in other industrialized nations. There is no clear, consistent evidence that any other meal frequency is better. In 2011 position stand, the International Society of Sports Nutrition reported that spreading calories out over more than three meals doesn’t appear to favorably change body composition. Eating breakfast, lunch and dinner each day may be optimal for controlling appetite and managing food intake.

Aiming for Optimal Calorie Distribution

One advantage of eating three meals a day is that you are spreading your calories across your day, so you don't get too hungry between meals. Another is that you aren't spreading your calories too thin, so you are more likely to feel satisfied after each meal. Grazing all day may cause you to loose track of calories, especially if you choose high-calorie snacks, while having fewer than three meals a day may leave you so hungry that it's hard to make healthy food choices.

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Why are Jeans so Popular?

Jeans have widely conquered the hearts and closets of people all over the world. People of all ages irrespective of any gender love to wear this piece of clothing. Since umpteen years jeans have found its place in the wardrobes of rich and poor, celebrities and common man. However, it has not lost its charm and is here to rule with its versatility.

It would not be wrong to say "jeans thy second name is fashion". Nevertheless we can see a transition in peoples choice of clothing. There is a shift from traditional wear to jeans all over the world. Clothing to a large extent depicts the social culture and tradition of a country. Jeans has been successful in replacing the traditional wear over the years in all countries of the world.

Let's get into the history of jeans. At first jeans was used by the working class men. It was thick, strong, and long lasting. In short a trouser that can survive in any conditions. This thick cotton cloth was made of "gene" material from Genoa, a city in Italy. Thus, it got its name.

Jeans were an instant hit among people doing tough physical work. A tailor from Nevada, Jacob Davis wanted to create jeans incorporating his new idea. He wanted to add copper rivets at places where it tears easily like the curve of pockets which often gets torn. This would not only strengthen the pants but also add to the style quotient of the trouser.

However, he did not have the money to patent in his name. Jacob Davis approached Levi Strauss with his idea to partner him in his venture. Strauss accepted this offer. In 1873, Levi Strauss patented the riveted jeans under both their names. They became popular instantly. With the passage of time it became renowned as 'jeans'. According to World denim market production and consumption report 2012, at present the world market for jeans is estimated to be over US $66 billion.

Moreover, over 50 percent of denim production is based in Asia with China, India, Turkey, Pakistan and Bangladesh. 70% of world jeans consumption is among EU, US and China. There are 513 denim mills worldwide. China alone has 297 mills, followed by 104 mills in other Asian countries, 46 in Latin America, 41 in Europe, 15 in Africa, 9 in North America and 1 in Australia. Americans alone purchase 450 million pairs of jeans every year.

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Why can't we predict earthquakes?

Scientists who study earthquakes say there is no method at present  which can predict the time and intensity of this natural calamity. While  the probability of an earthquake can be estimated, those claiming to  predict the exact date and time are just fooling the public.
According to United States Geological Survey (USGS), one of the  most reliable and technically advanced organization involved in studying  earthquakes, scientists are unlikely to be ever be able to predict  them.

"No, and it is unlikely they will ever be able to predict them.  Scientists have tried many different ways of predicting earthquakes, but  none have been successful. On any particular fault, scientists know  there will be another earthquake sometime in the future, but they have  no way of telling when it will happen," the USGS says.
In reply to another question - is there such a thing as  earthquake weather? Can some animals or people tell when an earthquake  is about to hit - USGS replies, "These are two questions that do not yet  have definite answers. If weather does affect earthquake occurrence, or  if some animals or people can tell when an earthquake is coming, we do  not yet understand how it works."
Seismologists and geologists universally agree that predicting an  earthquake is not possible. They say that while there is always a  chance of a major earthquake in a geologically active area like the  Himalayas where the Eurasian and Indian plates meet, there is no  scientific method to find out in advance the date, time and intensity of  such a temblor.
On the basis of scientific data and studies, the probability of a  future earthquake can be calculated, but even then it is not very  accurate.

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