A magnet is a material that attracts any objects that contains iron. Magnet has arranged domains (what makes them have the magentic property), than other objects. The properties of magnet include, iron, nickel, and cobalt. Just like the electric charges, equal signs repel each other, and opposite charges attract. Also, to add, there are natural magnets that naturally have magnetic mineral call magnetite.
In the further chapter, there would be variety of different magnets including ferromagnet, electromagnet, temporary magnet, and permanent magnet.
EM10. I can describe how the magnetic domains are arranged in a magnetic/non-magnetic material.
In a magnet, the domains are aligned in one direction forming a 'charge'. In non magnetic material, domains face different directions cancelling each other. *In a magnetized material, all or most of the magnetic domains are arranged in the same direction*
EM11. I can explain the connection between electricity and magnetism (electromagnetism).
The connection between electricity and the magnetism is that they both form magnetic field. As current goes trhough a wire, it produces certain magnetic fields that can be utilized for electric motor.
This can be proven through an experiment involving compasses surrounding the wire. When the DC energy source is turend on, the compasses starts to change its direction, due to the magnetic field produced from the wire.
EM12. I can outline the difference between DC/AC current and its uses
DC is an initial for direct current. It was founded/utilized by Thomas Edison, who opened a generating plant in New York City. Direct current can be produced by going through a process of changing magnetic field or produced from a energy source such as a battery.
AC stands for alternating current. In 1888 Nikola Tesla, who worked for Thomas Edison, invents a system of distributing alternating current. AC as it means, is a current that can change its flow of direction. It consists of charges that moves back and forth in a circuit. The advantage that AC has over DC is that voltage of AC can be easily controled. "This means that a high voltage can be used to send electrical energy over great distances. Then the voltage can be reduced to a safer level for everyday use." (p.97)
EM13. I can explain why the Earth behaves like a magnet and the consequences of it.
The Earth's outer core is believed to be composed of primarily nickel and iron (in liquid form). As the convection occurs, the liquid metal flows very quickly, creating electrical current that ultimately produces Earth's magnetic field. this is called the "Dynamo Effect." In addition, through this process, the Earth gets a sphere call the magnetosphere that extends around the Earth up to thousands of miles. This sphere gets continuously distroted by sun's stream of charged particles. With this, we get a protection from the solar wind.
A common theory related to this is that the Earth occasionally reverses itself. The strongest part of the field gets weakened, but the weaker side of the field remains. The pole last reversed around 780,000 years ago. We are currently undergoing another reversal, but it would take thousands of years to be complete.
(the picture changes)EM14. I can explain the importance of grounding wires and using fuses/circuit breakers.
The ground wires provide an additional electrical path that is independant from the normal current carrying path. This parth is connected to the electrical neutral service panel, guaranteeing a low enough resistance to trip the circuit breaker.
Circuit breaker and Fuses limit the flow in a current. The metal filament in the fuses melt when receives certain voltage, stopping the current from further passing. Circuit breaker works the same, however, when they receive certain voltage, the bimetalic strip gets banded. Once they get activated, fuses has to be refilled, and the breakers can just be fixed.
Ground wire and the Circuit breaker/fuses are standard safety devices used in standard electric circuits.
EM15. I can explain how an electromagnet works and cite applications for them.
Electromagnet is created and works very easily. You just need a nail, copper wire, and a battery. First, you wrap the nail with a copper wire in one direction, so it can have a certain direction of magnetic field. This would be called the solenoid. Then, you connect the wire with the battery, making it to have electrons to flow and create a current. Whenever you connect the wire to the battery, it will have the magnetic field.
Electromagnet is used in vareity of electric appliances nowadays. It is used in computers and earphones. What would happen if a magnet disrupts a electromagnetic field?
I know this because I have experienced this through my earphone. when a magnet disrupts the electromagnetic field, the electrons inside the wire gets altered, and cause a problem.
EM16. I can explain how a simple motor works (parts and function).
Electric motor is a way to change electrical energy into a mechanical energy.
There are three parts in an electric motor. Commutator, Brushes, and an armature. Commutator is the part where it allows electric currents to enter the armature. Commutator will have a spinning motion, reversing the direction of current in every half turn.
Brushes are the part where it touches commutator, and transfers the electric currents.
Finally, Armature is the part where electric currents flow through.
In a simple motor, there is an DC energy source, commutator, brushes, armature and a permanent magnet.
As electric currents go through a armature through brushes and commutator, the magnetic forces exerted by them gets rejected by the permanent magnets. This results spinning motion. As the half turn occurs in the commutator , the direction of electric currents reverses allowing the process to repeat non-stop.
EM17. I can describe how a generator and a transformer work.
Opposite from the motor, a generator is a device which makes mechanical energy into an electrical energy. As long as there is a force to turn the turbine, an electrical energy is produced. There are variety of generators. Moreover, among all, one of the most efficient one would be the nuclear power plant. It uses direct heat energy from the explosion of Uranium 236 to push the turbine, and produce electrical energy.
A transformer is an electrical device used to convert AC power at a certain voltage level to AC power at a different voltage, but at the same frequency. According to the wraping that has been done on the side, it decides whether it would increase the voltage or decrease.
EM18. I can explain the importance of transformers to power grids.
The fact that a transformer can change the voltage is one of the most significant point. Whenever, the electricity is coming from the far distance, it is pushed with high voltage to cover up the speed and the distance. This voltage obviously wouldn't be fit for the house appliances and other elctric using sources. Therefore, the transformer, adjusts voltage for our house to utilize it.
EM19. I can explain methods of power production and distribution.
There are several ways of producing electricity. Using renewable sources, such as wind, water, sun, geothermal power. Using coals, and using nuclear energy. As mentioned before, using the nuclear energy is the most productive one. One common thing that all these energy sources have is that they are all interacted with spinning the electric generator.
Once they all spin the electric turbine, the electrical energy gets distributed through transformers. These electricity pass through several transformers, and enter our house with safe rate of strength.
EM20. I can describe the differences of 110v/220v and main advantages and disadvantages of each.
110v and 220v. As it is written, 110v has weaker voltage then 220v. I personally prefer 220v because it has stronger push and make things work faster. For example, when heating the bath water, 220v would most likely make the water warmer in a shorter period of time because it makes electric currents to pass a certain point much faster. P=VI. Also, since Voltage is high, it would require much less Currents to produce same power as 110v source. In this perspective, we can say that 220v source is much more productive.
The disadvantage is that it should be safely cared since it may cause some danger with the high voltage shock.
Its advantages are: It is clean source of energy. Doesn't cause any pollution nor produces eco-harming substances. It can be transmitted quickly, and used widely all over the world. In fact 90% of the appliances that we use require electricity.
electrical is also advantageous because it can restart people's heart.
One disadvantage would be that it should be cared safely, or else it can shock people.
