A Rocket Engine

A rocket engine is symply a jet engine that carries its own supply of oxygen. But have you ever think how a rocket can launch into space? Hope this could answer your question.


A rocket is made from three parts of stage. At the bottom of a rocket engine contains with fuel and oxygen tanks is called the first stage. When it blasts off, the first stage lifts the whole rocket high into atmosphere. The first stage engine stops because the fuel and oxygen have been used up. Now the first stage is separated from the rest of the rocket, and drop away. Thus the rocket is rid of all the weight of the first stage.


The second stage engine starts up. Because the rocket is now lighter, it can go farther with the fuel remaining. When the second stage engine runs out of fuel and oxygen, the second stage is separated, and drop away. Now the rocket is lighter still. The third stage engine starts up and hurls the payload of instruments or people, into space.


That is how a rocket with people like satellite, or astronauts and all the instrument can reach the moon. Hope this information can be useful to us.

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The Making of a Cloud into a Rain Drop

If you have ever been on the beach,  you probably noticed that  you felt warmer or hotter on the beach than when you were in the water. This means that the air over the beach is warmer than the air over the water.  The warmer air over the beach rises, goes up like invisible smoke. The warmer air rises because the cooler air from over the water flows in and pushes it up and becomes a cloud.

A cloud is made up of tiny droplets of water, hanging in the air and it is made from condensed water vapor.  You might wonder why these water droplets stay up in the sky. Well, remember that they are in rising air. The droplets are so small and light that all the rising air can keep them from falling. Indeed, the rising air may sweep them up higher and build a towering cloud.

A cloud is a collection of tiny droplets of water. They are so tiny that it would take about one hundred of them side by side to reach across the head of a pin. It takes a million cloud droplets to make one raindrop. the tiny droplets moving about in the rising air come together  to make larger droplets. The larger droplet is heavier than the small ones. It starts to fall. As the larger droplets falls, it collides with more small droplets. These collisions make a larger droplet larger still and becomes a raindrop.

The raindrop may have still more collisions as it falls. It may get still bigger, so big that it cannot go on as one raindrop. It breaks into smaller drops. Each of these smaller drops now has collisions with droplets, and starts growing. It is a kind of chain reaction. One drop leads to others, and others, and others. At last some drops fall out of the cloud and fall to the ground. It is raining.

But there is another way in how a cloud making raindrops. The droplets may be carried so high by the rising air that they are turned to crystal of ice. The air has to be very cold for this freezing to happen. These crystal of ice get larger and larger, they get heavier and begin to fall through the cloud. As they fall, the crystals of ice get into warmer air. If the air is warm enough, they melt and become raindrops. If the air is not warm enough, the crystals fall to the ground without melting, and you will see these crystal of ice falling from the sky or you will see a snow...

If you want to make your own cloud, watch this video and have some fun experiment:

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The growth of a green plant

Do you really know how a green plant can grow? Some people thought they knew the answer already. Some people might say the answer is because we give water to the plant, or because of the sun, or because the plant takes substances from the soil to grow. None of these answer is wrong, but still cannot explain how. In this article, we will start an easy learning about how a green plant grows.

The first investigation about a green plant was set up by a Belgian scientist named Jan van Helmot in the year of 1605. He found that a willow tree took substances from the soil to grow. He found that plants needed water to dissolve the substances in the soil.

Green plants take two kinds of substances from the soil. One is called Nitrates, which are compounds of Nitrogen and Oxygen. The other one is called Phosphates, compounds of Phosphorus and Oxygen. Different kinds of plant needs different amount of these substances. As a green plant grows, the substances in the soil will be decreasing. That is why we need Fertilizers as an addition substances to be put back in the soil.

First investigation had proven that green plants need water to dissolve the substances, that is why we need to water the plant. But after many investigation, it was found that green plants also use substances that they took from the air, called Carbon Dioxide. Green plants can make foods for their lives such as sugars and starches from carbon dioxide and water.

But not only that, green plants also need heat and light to make food from substances dissolved in water and from Carbon Dioxide in the air. The heat and light that green plants need is come from the Sun.

Now we know what makes green plants grow. The information presented above will do one of two things: either it will reinforce what you know about  or it will teach you something new. Both are good outcomes.

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The Background of Perfume And Fragrances

Perfumes have been used since Egyptian times, and come in many different scents, formulas, and brands. The power of perfume and fragrances is often felt, as scent is a trigger of memories and feeling. This article discusses the basics of what makes up perfumes, and the different types of smells that are known in perfumery world.

There is science and art behind the chemistry of a well made fragrance. It is not designed to be smelled one time, especially not directly from a bottle spray. The best way to experience the full potential of the bouquet is to spray it on a piece of paper, and hold onto it for at least thirty minutes. Through this time, take notice of the notes to fully know all smells the brand provides.

What you are looking for after spraying a sample spritz are three distinct aroma notes. The first note is called a top note, because it is the initial scent you notice right after the first spray. This should eventually lead to the heart note, which is the main smell of the fragrance. This first scent should last the longest. As the scent fades you smell the final note, which is less potent than the heart note.

The different types of fragrance are divided into something called the fragrance wheel. The fragrance wheel is split into four varieties of scent, floral, oriental, woody, and fresh. These four scents are distinguished from each other for moods they set, and appropriate times of day to wear each particular type.

The florals are known as romantic, girly, and luxurious scents. They do best for everyday, daytime wear. Orientals are richer in smell, and often associated with mature, professional women. They are usually worn during evening events. Fresh smells are suitable for every day, and not as distinctive as florals or orientals. They are often worn by young people who aren't looking for an overwhelming smell. Woody scents are traditionally associated with men cologne, as they have a musky, masculine smell.

The people who design and create perfumes are called perfumers, and they are involved in a very complex and precise process. The different scents combine to create the notes of a fragrance, and of these scents perfumers choose and pick the primary scents, modifiers, blenders and fixatives .

The source of fragrance smell is often very potent and highly concentrated, and may be abrasive to the skin. In order to have perfumes that have different strengths, there are general rules for formulations available. If you look at a bottle of perfume, you will often notice it says one of these things: eau de cologne, which is two to five percent potent scent, eau de toilette, which is made up at five to twenty percent, eau de parfum, ten to thirty percent potent, or perfume extract, which the strongest scent at twenty to forty percent.

Having a signature scent isn't to hard, especially since, due to body chemistry, perfume and fragrances smell different on everyone. It may take a little time to find a brand and type you like best, but now you know a little bit on the background of perfume making and what goes into creating a bottle of fragrance.

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The Invention of Telephone

When you're learning about something new, it's easy to feel overwhelmed by the sheer amount of relevant information available. This informative article should help you focus on the central points. This article explains a few things about telephone, sound waves, electromagnet waves, transmitter, receiver and if you're interested, then this is worth reading, because you can never tell what you don't know.

The Invention

Having found that a message can be sent through an electromagnetic waves,  some scientists wondered whether  a sound  message  can also be sent through a wire. A scientist named Alexander Graham Bell finally managed to create a tool that can deliver sound messages. The tool that we've known as the Telephone. There's no need to write about how Bell invented the telephone because there has been so many articles about it. Let's focus on the telephone itself.

How does a telephone work?
Telephone has two important components to send and to receive messages. To send a sound message requires a Transmitter to change the sound into a varying electric currents. To receive sounds needed a tool called Receiver that converts varying electric currents, which transmitter has sent, into sound.

In the previous article about Echo, it has been explained that when we make a sound then our vocal chord will vibrate and release sound waves. If the sound waves are received by our ears then we will be able to hear the sound. In the telephone, our sound waves are changed into varying electric currents. When we speak, our sound waves strike a disk of thin metal in the telephone transmitter. Our sound waves make this disk vibrate and change this vibrate into pattern of electric currents. This electric currents have the same pattern as the vibrations of the disk and the vibrations of the disk has the same pattern as our sound chord vibrations / our sound waves. The electric current travels along a wire and changed back into sound by the receiver. But how?

The receiver has two main parts : an electromagnet and a thin disk of iron. when electricity passes through the electromagnet, the electromagnet attracts the iron disk. When the current stops, the disk will spring back. Varying of electric current will make the disk move back and forth or vibrate. Because the electric current has the same pattern with our sound waves so the disk will vibrate in the same pattern. As the disk vibrates, the disk will make sound waves with that pattern. Finally, our ears will catch that sound waves and translate it into sounds. That is how we can hear the sound through a telephone.

Hopefully this articles above has contributed to your understanding about telephone and how it works.  So never stop reading, never stop learning, and never stop sharing with others.

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Making Our Own Telegraph

This time I wanted to share the knowledge about how to make a telegraph by simple and use it to send a message. I read in a book of science, to be honest I myself have never tried to built  it, but I might try sharing here. Hopefully useful.

The first one we need:
- 3-inch bolt
- 3-inch nail
- Iron hinge
- Metal strips
- Bell wire
- Screws
- Rubber band
- Batteries 1.5 v
- Woods as shown in the picture

First make a telegraph sounder and key, assemble materials as shown in the picture below. Use a tin cans to make the metal strip for the key.

When you turn on the current by pressing down the key, the hinge should go up and touch the bolt with click sounds. Adjust the height of the electromagnet, if necessary, by turning the nut.
When the current is off, the hinge should drop back on the nail with another click. If the hinge stays up, adjust the pull of the rubber band.
This picture below shows how two sets telegraph Should Be connected. Use the International Morse Code  to send your message. Happy experimenting ....

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Telegraph : First Wired Long Distance Communications Tool

This article will discuss about the Telegraph and the work of a telegraph. Who would've never heard the word 'Telegraph', yes it is a tool for a long-distance communication that first created in the world and became a breakthrough for communication tools that we use today. First prototype of the telegraph tested and introduced by Carl Gauss and Wilhelm Weber in the 1830s, but this technology still could not be launched until Samuel Morse perfected it at the end of 1830. It did not take long to make the cities and countries were linked by telegraph wires. The job of a telegraphers looked very glamorous and exciting for young men at that time, one of which was famous named Tom Edison.

Then How a telegraph can send message?
Telegraph is designed to transmit electricity and turn it into electromagnet. There are three parts in the telegraph instrument.
- a key, to send the message
- a sounder, to receive the message
- a source of electric energy: dry cells
The key is a simply push-button switch design for high speed use, and control the flow of electric current. The knobs on the key can be adjusted so that a small movement of the key controls the flow of current precisely.

 

This is how :

Push down the key and the contact point will be touched, electrons will flow through the key from the dry cells to the sounder. The electric current goes through the two coils of wire on the sounder and back to the dry cells. The coils become electromagnets and attract the iron cross piece, which attached to the sounder bar. The sounder bar will be pulled down quickly, hits the frame under it and makes a loud 'click' sound.
To send a message you need a code, most telegraphers use International Morse Code. The letters are represented by combination of dot(.) and dash (-). To send a 'dot', press the key and let go immediately. To send a 'dash' press the key and hold for about the time to say "dash". A dot is a short interval, and a dash is a longer interval.

Now you know how a telegraph works. In the next article I will try to describe how to make a model of telegraph. If you could build them, try to use this International Morse code, like the picture below, to send your message.

I hope that reading the above information was both enjoyable and educational for you. Your learning process should be ongoing--the more you understand about any subject, the more you will be able to share with others.

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The Chemical Change in a Candle

The following article includes pertinent information that may cause you to reconsider what you thought you understood. The most important thing is to study with an open mind and be willing to revise your understanding if necessary. If you don't have accurate details regarding science, then you might make a bad choice on the subject. Don't let that happen: keep reading.

We all must have been familiar with candles. Yes, a thing that can give light in darkness. But have we ever wondered how a candle can light a fire? In this article I will try to describe it in a concise and hopefully easy to understand.

Candles made of flammable substance called paraffin. In a paraffin wax contains  the element Carbon (C).  When paraffin exposed to fire, the molecules in the paraffin will turn into another molecules form contains of  carbon. This molecules is floating around the fire and the candles, and the candle combines it with Oxygen  (O2) from the air into Carbon Dioxide (CO2) and produce an energy. The energy is light and heat. When we look at the size of a burned candle, the candle will slowly shrinking. It is not because the fire consumes the candle, but because the paraffin wax has been changed into energy molecules that produce fire and heat. The life of fire relies heavily on the paraffin wax, so when the paraffin has gone there will be no other energy that can provide fire and heat. This is what we call a chemical change

The changing process of  paraffin  molecules into a fire can not be seen with our eye. But try to look at when we blow out a burning candle, when the candle is out, there will be milky white smoke coming out and also the smell of  paraffin. This is because  paraffin has been changed back from the energy molecules into smoke before it disappears along with the air. This white smoke is the rest of paraffin that has not turned yet into a  flame because there is no source to generate fire and heat anymore.

Paraffin can not be lit by themselves. Like the fire that needs a paraffin wax, but paraffin also needs a fire source to be able to create a flame. Now we will prove through a small experiment that the smoke comes out from a candle when it's blown out is the paraffin molecules that turns into smoke. My friends thought that I used some magic trick when I did this : ). There is no magic in this thing, it is completely science.

Things to prepare:

1..Set up a candle and a match.

2.Light the candle with a match until the flame of the candle burns perfectly.

3.Then blow the candle until the flame dies and the white smoke comes out from the candles.

4.Light your match and direct the fire into the smoke but  not too far from the wick.

 

5.Don't be too long because the fumes of paraffin will soon be gone with the air and  the smoke is left only a residue of burning wick, so it won't work. Try it and Abracadabra ... see for your self that the candles can be lit without you touching the wick.

   

So now you know a little bit about science. Even if you don't know everything, you've done something worthwhile: you've expanded your knowledge.....  

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What is an Echo?

Have you ever gone to mountain or a valley? If you get there try to shout "Hello" then within seconds there will be a voice that respond. Whatever you shout that voice will say the same thing. That's not a ghost voice but our voice is returning. This is what we call an echo.

The word Echo comes from the Greek. In ancient times in Greece echo is described as the voice of a girl named Echo who fell in love with a man, but unfortunately he did not love her. Eventually the girl disappeared, she faded away and nothing was left but her voice.

How the sound returns

Echo comes from our own voice back due to the reflection. When we shout, our vocals cords vibrate and produce sound waves and the waves will travel through the air. If the sound waves hit a solid materials such as walls or mountains, the waves will bounce and head back. In short time the returning sound waves reach your ears so you can hear it.

Why we cannot hear the echo in our house

There are several requirements to make an echo. First there must be a high sound like when we shout, then number two there must be a solid molecules for the wave to bounce back. A sound has a very high speed. It could reach about 1100 feet in 1 second. We will not be able to hear echo if the distance where the sound waves bounce is too close because a sound needs time to travel. If you say "Hello" to a wall close to you, the sound does bounce from the wall but it goes to you in so little time that you cannot make it out. For your experiment you could go to a mountain, bring your stopwatch and start to count how long it will take for your sound to return.

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