Category Science

An insulator is the opposite of a conductor. It is a material that will not allow electrical current to run through it because its electrons are not free to move. Plastic is a very good insulator. That is why it is used to cover copper wire. The wire can then safely conduct electricity along its length without allowing it to come into contact with other conductors.

An electrical insulator is a material that does not easily allow flow of electricity through an electric current. Materials typically used to insulate include rubber, plastic and glass. In transformers and electric motors, varnish is used. Insulating gases such as Sulfur hexafluoride are used in some switches. Wires that carry electric currents are usually insulated so the electricity goes to the right place.

Insulator can mean not only the material but things that are made of that material. They are made of various materials such as: glass, silicone, rubber, plastic, oil, and wood, dry cotton, quartz, ceramic, etc.

The type of insulator will depend on the uses. Insulators have high electrical resistivity and low conductivity. The insulators prevent the loss of current and make the current more efficient by concentrating the flow.

• The pin insulator is the earliest developed insulator. Pin type insulators can have up to three parts, depending on the amount of voltage.
• The suspension insulator is for voltages above 33KV. Multiple insulators are connected in series.
• The strain insulator is the same as a suspension insulator but it is used horizontally, whereas the suspension insulator is used vertically. The strain insulator is used to relieve the line of excessive tension, which happens when there is dead end of the line or sharp curve. 

A circuit is a path along which an electric current can flow. Each part of the circuit must be connected to the next, and each must be able to conduct electricity. In a series circuit, there is only one path for the current to follow, and it passes through each component of the circuit in turn. If one component fails, the current will no longer be able to flow. Christmas tree lights are usually connected to each other in series. When one bulb blows, the circuit is broken and all the lights go out.

Instead of being connected in a series circuit, the same components could be connected in a parallel circuit. In this kind of circuit, there is more than one pathway for the electrical current to flow along.

An electric circuit includes a device that gives energy to the charged particles constituting the current, such as a battery or a generator; devices that use current, such as lamps, electric motors, or computers; and the connecting wires or transmission lines. Two of the basic laws that mathematically describe the performance of electric circuits are Ohm’s law and Kirchhoff’s rules.

Electric circuits are classified in several ways. A direct-current circuit carries current that flows only in one direction. An alternating-current circuit carries current that pulsates back and forth many times each second, as in most household circuits. (For a more-detailed discussion of direct- and alternating-current circuits, electricity: Direct electric current and electricity: Alternating electric circuit.).) A series circuit comprises a path along which the whole current flows through each component. A parallel circuit comprises branches so that the current divides and only part of it flows through any branch. The voltage, or potential difference, across each branch of a parallel circuit is the same, but the currents may vary. In a home electrical circuit, for instance, the same voltage is applied across each light or appliance, but each of these loads draws a different amount of current, according to its power requirements. A number of similar batteries connected in parallel provide greater current than a single battery, but the voltage is the same as for a single battery. 

The network of transistors, transformers, capacitors, connecting wires, and other electronic components within a single device such as a radio is also an electric circuit. Such complex circuits may be made up of one or more branches in combinations of series and series-parallel arrangements.

A lightning conductor is a metal rod that is placed so that it points upwards above the highest point of a tall building. If lightning does strike the building, it is the lightning conductor, not the building itself, that the spark hits. The electrical charge then runs harmlessly down the lightning conductor to Earth.

Lightning rods were originally developed by Benjamin Franklin. A lightning rod is very simple — it’s a pointed metal rod attached to the roof of a building. The rod might be an inch (2 cm) in diameter. It connects to a huge piece of copper or aluminum wire that’s also an inch or so in diameter. The wire is connected to a conductive grid buried in the ground nearby.

The purpose of lightning rods is often misunderstood. Many people believe that lightning rods “attract” lightning. It is better stated to say that lightning rods provide a low-resistance path to ground that can be used to conduct the enormous electrical currents when lightning strikes occur. If lightning strikes, the system attempts to carry the harmful electrical current away from the structure and safely to ground. The system has the ability to handle the enormous electrical current associated with the strike. If the strike contacts a material that is not a good conductor, the material will suffer massive heat damage. The lightning-rod system is an excellent conductor and thus allows the current to flow to ground without causing any heat damage.

Lightning can “jump around” when it strikes. This “jumping” is associated with the electrical potential of the strike target with respect to the earth’s potential. The lightning can strike and then “seek” a path of least resistance by jumping around to nearby objects that provide a better path to ground. If the strike occurs near the lightning-rod system, the system will have a very low-resistance path and can then receive a “jump,” diverting the strike current to ground before it can do any more damage.

As you can see, the purpose of the lightning rod is not to attract lightning — it merely provides a safe option for the lightning strike to choose. This may sound a little picky, but it’s not if you consider that the lightning rods only become relevant when a strike occurs or immediately after a strike occurs. Regardless of whether or not a lightning-rod system is present, the strike will still occur.

If the structure that you are attempting to protect is out in an open, flat area, you often create a lightning protection system that uses a very tall lightning rod. This rod should be taller than the structure. If the area finds itself in a strong electric field, the tall rod can begin sending up positive streamers in an attempt to dissipate the electric field. While it is not a given that the rod will always conduct the lightning discharged in the immediate area, it does have a better possibility than the structure. Again, the goal is to provide a low-resistance path to ground in an area that has the possibility to receive a strike. This possibility arises from the strength of the electric field generated by the storm clouds.

Static electricity is what sometimes makes a nylon jumper crackle and spark in dry weather. Or you may, get a small electric shock from a metal surface after walking across a carpet made of artificial fibres. Rubbing something made of amber or plastic can cause it to pick up electrons from your clothes or hair, giving them a positive charge. If you then touch something with a slightly negative charge, a small spark may fly across just before you touch it, or, if it is light, the oppositely charged object may be attracted to you.

Static electricity can be a nuisance or even a danger. The energy that makes your hair to stand on end can also damage electronics and cause explosions. However, properly controlled and manipulated, it can also be a tremendous boon to modern life.

“Electric charge is a fundamental property of matter,” according to Michael Richmond, a physics professor at the Rochester Institute of Technology. Nearly all electric charge in the universe is carried by protons and electrons. Protons are said to have a charge of +1 electron unit, while electrons have a charge of ?1, although these signs are completely arbitrary. Because protons are generally confined to atomic nuclei, which are in turn imbedded inside atoms, they are not nearly as free to move as are electrons. Therefore, when we talk about electric current, we nearly always mean the flow of electrons, and when we talk about static electricity, we generally mean an imbalance between negative and positive charges in objects.

Electricity is a form of energy. Electricity is the flow of electrons. All matter is made up of atoms, and an atom has a center, called a nucleus. The nucleus contains positively charged particles called protons and uncharged particles called neutrons. The nucleus of an atom is surrounded by negatively charged particles called electrons. The negative charge of an electron is equal to the positive charge of a proton, and the number of electrons in an atom is usually equal to the number of protons. When the balancing force between protons and electrons is upset by an outside force, an atom may gain or lose an electron. When electrons are “lost” from an atom, the free movement of these electrons constitutes an electric current.

Electricity is a basic part of nature and it is one of our most widely used forms of energy. We get electricity, which is a secondary energy source, from the conversion of other sources of energy, like coal, natural gas, oil, nuclear power and other natural sources, which are called primary sources. Many cities and towns were built alongside waterfalls (a primary source of mechanical energy) that turned water wheels to perform work. Before electricity generation began slightly over 100 years ago, houses were lit with kerosene lamps, food was cooled in iceboxes, and rooms were warmed by wood-burning or coal-burning stoves. Beginning with Benjamin Franklin’s experiment with a kite one stormy night in Philadelphia, the principles of electricity gradually became understood. In the mid-1800s, everyone’s life changed with the invention of the electric light bulb. Prior to 1879, electricity had been used in arc lights for outdoor lighting. The lightbulb’s invention used electricity to bring indoor lighting to our homes.

Electricity is a very flexible form of energy. It can easily be converted to heat, light or sound energy. It can be carried long distances through wires and cables. It is clean and safe if used in the right way. In fact, electricity is now so much a part of our lives that it is difficult to imagine being without it.

Electricity is one of the most important blessings that science has given to mankind. It has also become a part of modern life and one cannot think of a world without it. Electricity has many uses in our day to day life. It is used for lighting rooms, working fans and domestic appliances like using electric stoves, A/C and more. All these provide comfort to people. In factories, large machines are worked with the help of electricity. Essential items like food, cloth, paper and many other things are the product of electricity.

Modern means of transportation and communication have been revolutionised by it. Electric trains and battery cars are quick means of travel. Electricity also provides means of amusement, radio, television and cinema, which are the most popular forms of entertainment, are the result of electricity. Modern equipment like computers and robots has also been developed because of electricity. Electricity plays a pivotal role in the fields of medicines and surgery too — such as X-ray, ECG. The use of electricity is increasing day by day.