Parabolic Velocity

in astronomy, the velocity a body would need to make a parabola about the centre of attraction (also called ESCAPE VELOCITY).

Taken from Dictionary of Science

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The velocity which an object at a given point would require in order to describe a parabola about the center of attraction. This is also the escape velocity since it is the upper limit of velocity on a closed curve. It is obtained by multiplying the velocity of an object moving in a circular orbit by the square root of 2 (approx. 1.414). For example, if the Earth's mean velocity around the Sun of 29.8 km/sec. (18.5 miles/sec.), in a near circular orbit, were increased to 42 km/sec. (26 miles/sec.), the Earth would move to a parabolic path and escape from the solar system.

Taken from The Internet ENCYCLOPEDIA OF SCIENCE

Galactic Rotation

the rotation of the GALAXY, and all its gas, stars and dust, which increases towards its centre. The rotation near the SUN is approximately 250 kms^-1 and to make one galactic orbit takes the Sun in the region of 250 million years.

Taken from Dictionary of Science

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The rotation curve of a galaxy can be represented by a graph that plots the orbital velocity of the stars or gas in the galaxy on the y-axis against the distance from the center of the galaxy on the x-axis. Stars revolve around the center of galaxies at a constant speed over a large range of distances from the center of the galaxy. Thus they revolve much faster than would be expected if they were in a free Newtonian potential. The galaxy rotation problem is this discrepancy between the observed rotation speeds of matter in the disk portions of spiral galaxies and the predictions of Newtonian dynamics considering the visible mass. This discrepancy is currently thought to betray the presence of dark matter that permeates the galaxy and extends into the galaxy's halo. An alternative explanation is a modification of the laws of gravity, such as MOND (Modified Newtonian Dynamics).

Taken from Wikipedia

Absolute Zero

the temperature at which the particles that make up matter have no energy at all whether due to heat or motion. It is theoretically given the value of -273.15°Celsius (-459.67° Fahrenheit).

Taken from Dictionary of Science
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Absolute zero is the temperature at which entropy reaches its minimum value. As implied by the laws of thermodynamics, absolute zero cannot be reached by artificial or natural means because this would require a system to be fully removed from the rest of the universe. A system at theoretical absolute zero possesses quantum mechanical zero-point energy. While all molecular motion does not cease at absolute zero, the system does not have enough energy for transference to other systems. It is therefore correct to say that molecular energy is minimal at absolute zero.

By international agreement, absolute zero is defined as precisely 0 K on the Kelvin scale and as −273.15° on the Celsius scale. Absolute zero is also precisely equivalent to 0 R on the Rankine scale (same as Kelvin but measured in Fahrenheit intervals) and −459.67° on the Fahrenheit scale. Though it is not theoretically possible to cool any substance to 0 K, scientists have made great advancements in achieving temperatures close to absolute zero, where matter exhibits quantum effects such as superconductivity and superfluidity.

For the kinematics of molecules at absolute zero on a larger scale, which is easier to understand, see kinetic energy.

Taken from Wikipedia

Identical Twins

two identical individuals which develop from a single fertilized egg that divides early on into two equal parts. Identical twins have the same genetic make up and are always of the same sex.

Taken from Dictionary of Science

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Twins are two offspring resulting from the same pregnancy, usually born in close succession. They can be the same or different sex. Twins can either be monozygotic (MZ, colloquially "identical") or dizygotic (DZ, colloquially "fraternal" or "non-identical").

Taken from Wikipedia

How should I cope with having braces put on my teeth in two weeks? I am afraid some of my friends will make fun of me.

A. Orthodontic work for teens is becoming more commonplace. I'm sure that you know others who have braces. Didn't you quickly get used to their new appearance?

Your worth to your real friends is more than just physical appearance. It won't be long before you're accustomed to your new braces and your friends will hardly notice. Remember, too, the purpose of your braces is to give you healthier and straighter teeth soon.

- Answer prepared by Victor Kubik, a minister of the Worldwide Church of God

Taken from Youth 90 magazine

How to Get a Boss

If you don’t have a job, but would like one, here are some things you can do to prepare for the working world.

Make a list of your skills. These may be technical, like typing, being able to operate a cash register or 10-key machine. They may involve special knowledge you’ve gained through classes or other activities such as sewing, cooking, repairing things, running a slide projector or working in a photographic darkroom.

Whatever your skill, have your teacher, club adviser or school counselor write a letter of recommendation stating what your skills are, what type of machines you can operate and so on. Take copies of these letters with you to your interviews.

Narrow your search. Do you want a job only to make money or do you want to gain experience in a certain area? Do you want an outdoor or indoor job? What hours can you work?

Prepare yourself. Type up your resume and make sure you have appropriate clothes for the job interview. Take a deep breath and…

Start looking early. For a summer job start looking at least a month before school is out. Ask friends, relatives and teachers if they know of any job openings. Look through the want ads and watch bulletin boards. If you want to work at a specific place, go see them to find out if they’re hiring. Even if they’re not now, when a job does open up they may remember your making that extra effort.

Make a good impression. Be on time for your interview, don’t chew gum and try not to be too nervous. Let your energy and enthusiasm show! Don’t be afraid to admit you lack experience, but explain that you have the desire to learn.

Don’t give up. Keep trying. Check back with a few places to see if anything new has opened up. Stay positive and you’ll soon be cashing your first paycheck!

- By Kathy Johnson

Taken from Youth 90 magazine

HOW TO MAKE YOUR BOSS VERY, VERY HAPPY!

By Jane Jones

Good workers not only keep their jobs, they receive raises. Here are some tips to help you be a valuable employee.

Jessica and Sherri just got their first jobs. They both work at shops in the mall near their homes.

One of them did quite well at her job. The other, well, flopped. I'm sure you'll be able to figure out which one is which.

Jessica came in late today, but she couldn't help it. (That's what she said yesterday, too.)

Sherri got stuck doing routine inventory again. She did it as quickly as she could and then went home exhausted.

Jessica got a new responsibility and called from work to tell her best friend about it. Of course, she also had to find out how the school football game had gone and what Jeff had said to Stephanie after Math class.

Sherri got sick and called to tell her boss she couldn't come in for her regular shift. She offered to work extra hours on the weekend to make up the time.

Jessica studied for her history exam while working with the day's receipts. Somewhere at corporate headquarters are her notes on World War II.

Sherri watched and listened a lot her first few weeks to pick up a feel for how the store operated. She found out quickly who worked hardest, what techniques worked best with the customers and how she was supposed to look and act while at work.

Jessica reluctantly worked a different shift to replace a girl who called in sick. She told the other employees that "Rene's probably faking it. I bet she just went to the beach." Rene heard about Jessica's comment and now the manager can't schedule them together or they'll fight.

Sherri politely helped everyone who came into the store.

Jessica ignored people she thought wouldn't be spending much money.

It doesn't take long to figure out which girl got fired and which stayed hired.

These scenarios are hypothetical, but according to employers, similar things happen every day. Many people don't know how to work. A few simple principles make the good workers stand out from the bad. Here's a brief list of some working world dos and don'ts:

Do:

• Remember you represent the company you work for. A customer may form an impression solely based on how you treat him or her. Sherri tried to learn as much as possible about hew work place so she could represent it well. Jessica cared more about herself than the customers.

• Make your first impression a good one: dress appropriately for your work place, keep your uniform (if you wear one) clean, keep yourself looking neat (especially notice hair and nails) and smile!

• Try to do more than is expected of you.

• Be honest.

• Watch and listen a lot.

• Call your boss if you can't make it to work.

Don't:

• Lie up to cover mistakes.

Mistakes you try to hide have a nasty way of creeping out just when you don't want them to. Admitting a mistake right away could save your employer money and you your job.

• Make a lot of personal telephone calls, talk to friends or do homework.

• Complain a lot or run another worker down.

• Bring your problems to work. Try to leave them at home so you can treat customers and fellow workers politely and give them your whole attention.

• Waste time. You're being paid to work, not goof off.

• Be afraid to ask your boss how you're doing. Ask how you can improve or take on more responsibilities.

• Be late.

• Be afraid to ask if you don't know how to do something. There's nothing wrong with saying you don't know something and offering to find out.

Your boss probably doesn't think work is the best place to catch up on "the latest."

Taken from Youth 90 magazine