Wednesday, April 10

Used Appliances


Introduction to used appliances:

Do you want that stunningly looking LED home theater television at Joe’s as yours? It’s not at all a big deal to own it. Just pay a visit to your nearest used appliances selling outlet. It won’t kill your urge to own one. I swear.

Second hand selling market is a trend everywhere around the globe. Anything is available for a reasonable price with reliable servicing offers. When you sell your old buggy television in order to get it exchanged with a new one, just remember one thing. Someone else is there to buy that product for a big amount of money for the same product that you just abandoned for a cheap price.



E-waste


It’s a real fact that many families with low living standards are enjoying their lives using these appliances that you consider as an e-waste. The stores that accept the used appliances may have a thorough check up on the products to find any inappropriate things that may cost as unfavorable while reselling it. They might give some advertisements carrying fancy words that the products they are selling are gently used, old reliable goods etc. It’s all are the methods to catch the attention of the middle class customers. They all win in that also.
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Selling of used appliances


The products are sold with a label of gently used goods. So through this label they can gain the trust of the customers. The customer comes to a used appliances shop to buy a product which he already knows much about. So the shop owner cannot play tricks on him much like he did while selling a new product. But he can hide any faults to some extent. For example, there is a CRT television displayed to get sold. The television might be having some faults like failing of picture tube to display after 10 minutes or like that. This type of faults can be easily hidden from a customer. Also the shop owner can argue and win that it is something that went wrong with the customer’s household electric connection that caused damage to the picture tube.

The used appliance market is a safer place to bargain if you are confident about the reliability of the product. Also you will get better service for that too. Most shops offer 30 days warranty for their products.

Universe Solar System


Introduction to Universe Solar System:

Family of the sun is given the name solar system. Sun is the centre of solar system. Nine planets are revolving around the sun in the elliptical orbits. The distnace of the planets from the sun and their velocities keep on changing as they revolve around the sun.

Some other heavenly bodies also revolve around the planets and are called satellites. These are also called moons of the planets. Some other heavenly bodies revolving around the sun are asteroids, comets and meteors etc.

Let us discuss about universe solar system and its objects in detail:

Description of universe solar system:

1. Sun:

- It is the nearest star that we can see.

- It shines of its own.

- It is also called luminous body of our solar system

- The mass of the sun is 1.99 x 1030 kgm and its diameter is 1.4 x 109 m.

- It is about 109 times the diameter of the earth.

- The average distance of the sun from earth is about 1.496 x 1011 m, which is called one astronomical unit (A.U.). It is a unit used for the measurement of large distances.

- Sun rotates about its axis from east to west and completes one rotation in approximately 30 days.

2. Planets:

- Planets appear to be bright and do not emit light of their own. They reflect light of sun.

- These heavenly bodies revolve around the sun in elliptical orbits.

- Nine planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. These planets are written in the order of increasing distance from the sun.


Some other Objects in Universe Solar System:


3. Asteroids:

- Asteroids are very tiny planets (pieces of large planets) revolving around the sun between the orbits of Mars and Jupiter.

- Like regular planets, asteroids also revolve in elliptical orbits nearly in the same plane as that of the earth.

- The largest asteroid is called Ceres having radius  350 km and the smallest one is having radius only 50 m.

4. Comets:

- Comets are made up of rock like material surrounded by large masses of easily vapourised substances like water, ammonia and methane.

- The comets revolve around the sun in elliptical orbits.

- As comets come closer to the sun, the water vaporizes due to heat of sun.

- The light of sun exerts a pressure on these vapours and forces them to move away from the comet in the form of a tail.

- Edmund Halley discovered a comet in 18th century named as Halley's comet. This comet completes its orbit around the sun in 76 years. It can be seen in the sky after every 76 years. Last, Halley's comet was seen from earth in April 1986.

5. Meteors:

- When comets break while approaching the sun, the smaller pieces become visible.

- When they enter earth's atmosphere and heat up due to friction, they catch fire while moving towards earth.

- Therefore, we see a streakof light during night.

- These 'shooting stars' are known as meteors.

- They are of different sizes and weights.

- Most of them are in small sizes, and get completely burnt and do not reach earth. These are called meteors.

- Some heavy meteors landing on the earth are called meteorites.

- One of the biggest meteorites fell in Siberia on June 30, 1908.

Adding Sugar to Water


Introduction to adding sugar to water:

Sugar is a crystalline carbohydrate. It comes from sugarcane. It is sweet in taste. When added to the water, the sugar particles break down into smaller pieces. These small particles then arrange themselves together with the water particles and form a liquid solution..Sugar particle will no longer be visible with our naked eyes.

Sugar is soluble in water. When you add sugar to water and dissolve it volume of water before sugar is added is lesser than the volume of sugar in water. When we add sugar to water, the sugar crystal dissolves and it goes into the solution. Infinite number of sugar cannot be dissolved in a fixed volume of water. When as much sugar is dissolved, the solution is called saturated solution. The saturation point is different at different temperature .more sugar is held in a water, if the temperature is higher.


Adding sugar to water:


The size of the sugar crystal increases by the following process

1) Add sugar to the boiled water and stir it., till it dissolves.
2) Pour the solution in a jar and cover it with a waxed paper.

3) Dip a cotton string in a sugar solution, take it out, and dry it for few days.

4) The string after drying should be suspended in sugar solution and left undisturbed for seven days. at the end of seven days ,we will see that the size of a sugar crystal has grown in size with sharp edges and smooth faces. Dissolve more sugar to water on heating. by this solution becomes supersaturated. And the process of crystallization begins, once the heated solution cools down.

Explanation to adding sugar to water:


Add a pinch of sugar to water and feed a plant. That has wilted. And is not watered for a few days. the sugar helps the plants to get back to normal quickly. But this doesn’t always work. If the amount of sugar in the soil becomes too high, it promotes a higher incidence of fungi and bacteria. A typical fungus that thrives on sugar is yeast. Excess amounts of yeast causes an increase in the risk of an infection to plants and humans.

Thursday, April 4

Planet With Largest Moon


Introduction to planet with largest moon:

A solid heavenly body that revolves around the planet is called its natural satellite or its moon. For example, moon is the natural satellite of the earth because it revolves around the earth. Moons do not have their own light. They reflect the sunlight falling on them and therefore, appear shining. Except Mercury and Venus, all planets have their own  moons. In general, moons are much smaller than the planets. We can see the earth’s moon by unaided eye. The other moons of other planets were discovered after the invention of astronomical telescope and a large number of moons were discovered only after the spacecraft flew past them. The different moons have different features; some of them are earth’s like moon having large number of craters. Some of the asteroids have moon also. The asteroid IDA has also a moon. The planet Saturn has largest moon named as Titan.


Largest moon with planet:


Saturn is the second largest planet of our solar system. Saturn is known as the Jovian planet, because its structure is like Jupiter. Voyager explore the Saturn in 1980 – 81. Saturn is the sixth planet of our solar system. Saturn is the only planet whose rings are visible form the earth’s based optical instruments. The rings of the Saturn are formed by particles of ice and dust revolving around the planet. The particles in the ring having size in nanometers to meters.


Characteristics of the Planet with largest moon:


The density of the Saturn is less than the density of water. The atmosphere of Saturn mainly contains hydrogen, helium and methane. Saturn has 62 moons at present. Out of 62 moons, 53 are well named. Titan is the largest moon of the Saturn. The atmosphere of Titan is nitrogen rich as like earth in early years. Saturn is flat at poles so that it rotates very fast on its axis. Saturn takes 10 hours 39 minutes to rotate on its own axis and 29.5 earth’s year to revolve around the sun. The wind blows at very high speed on Saturn. The size of Titan is more than the size of planet Mercury.

Wednesday, April 3

Negative and Positive Wires


Introduction to negative and positive wires:

Let us first discuss about electricity, which can pass through the wires. There are two types of current, one is called the alternating current, which is used, in electrical mains and the other is called direct current, which is used, in the car’s light and in the radio. Direct current is obtained by the battery.  Let us discuss the wires, which carry the electric current.


Types of Negative and positive wires


Generally, there are three types of the wires:

Positive wire,
Negative wire and
Ground wire


In case of direct current, the positive wire is the wire, which carries 120 V. Negative wire is the wire, which has about 0 V. Ground wire is actually connected to the ground. Negative wires should be at zero potential or close to zero potential. It is the central point between the two phases of the electrical service coming to your house from the transformer on the electrical pole. Positive wire is the wire, which supplies the electric current to the electrical appliance. It is supplied to the devices in your home through a set of circuit breakers or fuses in older homes. It is wired directly to the outlets, and goes to the permanently installed lighting through the permanent wall switches. There is a standard colors in house wiring are: positive wire is of red color, negative wire is of black in color and the ground wire is of green in color.


Conclusion for negative and positive wires


Some of the devices in our daily life have only two flat prongs, and some have the third, round grounding prong. The two-prong devices are typically low current, low-power devices like lamps, bulbs, clock radios, can openers and the like. The third prong generally appears on higher-powered devices: washing machines, vacuum cleaners, televisions, computers, leaf blowers, drills, etc. This is usually done for safety reasons. This is also, why miswired outlets are dangerous: if the neutral and hot are reversed, the appliance will work just the same. However, if the appliance fails, the 'stray' energy remains under the 'top' insulating layer (next to the user), Not in the bottom one, putting the user at much greater risk. In older tools with metal cases, the user would actually get electric shocks in this event.

Wednesday, March 27

Home Electric Power


Introduction to Electric Power:

Electricity or electric power is generated at place far away from where it is to be consumed. The electric power is transmitted over long distances at high voltage which is gradually reduced by using step down transformers to 230 V, at which it is supplied to our household. Before, the power lines are connected to the electric meter which records the units of electric power consumed, a fuse is connected. This is known as company fuse. I like to share this Basic Kinematic Equations with you all through my article.

The wires coming out of the meter are connected to a main switch. When the main switch is on, then only the house receives power. After the main switch another fuse is provided, known as the consumer’s fuse. The main switch is a double pole switch. It has iron covering. The iron covering is earthed. The switch and the meter are locally earthed. From the meter the connections are taken to the distribution board.


Elecrical power system types


There are two types of wiring system

1. The tree system

In this system, the connections are taken from the distribution board to different parts of the house, each connection resembling a branch of a tree. Each connection is taken through a fuse F. It should be noted that different connections are taken in parallel, so that when the fuse in one part blows off, the remaining parts are unaffected.


2. The ring system

The ring system consists of a ring circuit starting from the main fuse box, which contains a fuse of 30 amperes. For each appliance a separate connection starts from the live part of the ring and ends on the ring. Since the power rating of each appliance is known therefore, connecting wires of proper current capacity can be used for each appliance. This makes it less expensive. Each appliance is connected with separate fuse, so that one fuse blows off the other appliances in the same room continue to work.

Earthing

To avoid this shock from the appliance, appliance is earthed. That is, we connect the metal case of the body to the earth which is zero potential. Besides the live and neutral wires, a third known as the earth wire is also provided.

Galaxy Definition


Introduction to galaxy definition:

We always observes that there are infinite numbers of stars in the sky. The question arises hat how are the stars distributed in the space. Astronomers have found that the starts are arranged in the huge groups. These groups are called the galaxies. The stars in the galaxy are held together by the gravitational attraction between them. Here we discuss about the galaxy.


A few points about Galaxy


Generally, a galaxy is the clusters of stars in the large amount. A component of the universe that has a huge group of stars and other celestial bodies bound together by the force of gravitation is called a galaxy. Apart from stars, a galaxy also has huge clouds of gases from which the new stars are born. A galaxy may have planets, moons, asteroids, comets and another celestial bodies. The number of stars in a galaxy can range about a million to hundred of billions. It is also estimated that there are over 100 billions galaxies in the universe and astronomers are discovering more every day. The galaxy in which our sun is located is called the Milky Way galaxy or Akashganga.


Types of galaxies


Galaxies have different shapes. Based on the shapes, mainly, three types of the galaxies are there, which are  Spiral galaxies, elliptical galaxies and irregular galaxies. In a spiral galaxy the stars forms a big spiral pinwheel. The Milky Way galaxy is a spiral galaxy. In an elliptical galaxy the stars are confined mainly in ellipsoid volume. An irregular galaxy does not have any particular shape.



Conclusion to galaxy


Most of the stars of the Milky Way galaxy lie in the disc shaped region, this region is called the galactic disc. The central part of the disc is thicker and bulges on both the sides. The density of stars in the bulge is much higher than that in the outer region of the galaxy. Milky Way galaxy is a large galaxy. The diameter of the galactic disc is about 100, 000 light years and its average thickness is about 70 light years.