RIGHT HAND RULE # 2

The right hand rule #2 determines the direction of the magnetic field around a current carrying wire and the other way around.

The curved fingers are around the conductor, the fingers show the direction of the magnetic field. The thumb is pointed in the direction of the convectional current.

The coiled conductor is grasped with the right hand so the fingers point towards the convectional current.

References:

1. The curved fingers are used to represent the direction of the magnetic field. Right-hand Rules. PhysicsEd.BuffaloState.edu. Retrieved February 27, 2012, from http://physicsed.buffalostate.edu/SeatExpts/resource/rhr/rhr.htm

2. (2008). Determining the Pole of the Magnetic Field – Right Hand Grip Rule. (2008). [Web Photo]. Retrieved from http://www.oneschool.net/Malaysia/UniversityandCollege/SPM/revisioncard/physics/electromagnetism/electromagnet.html

EARTH AS A MAGNET

The Magnet in Earth

The earth has an inner core that is made of pure iron, when this core is moving it creates an electric current that causes an invisible magnetic field to appear. You can think of the core as a magnet, the south end is pointing at the North Pole and the north end is pointing at the South Pole. This is based on the “opposites attract” rule, because of this rule the needle on a compass always points towards the North Pole. The needle has to be made of a lightweight magnet or the Earth's field won’t have enough strength to move it. The diameter of the earth is approximately 8000 miles; this means the magnetic field is very weak and has to travel a long way before it has any affect.  

When one sees a compass and the needle is pointed straight north, they assume that the needle is pointing straight towards the North Pole, this assumption is wrong. In reality, the needle is pointing at a slight angle because of the tilt. The north magnetic pole is currently located near Bathurst Island in northern Canada and the South magnetic pole is located near the continent of Antarctica. Every year, the poles can switch there places up to 10km, so where they are now they won’t be exactly there next year.  This is caused by climate change and other factors, preventing the magnetic field to stay in one place.

Present Day

In current times, the magnetic field has weakened by 10%. This could be because of rising sea level or climate change. However, geologists and scientists have said that it is not a matter that society should take seriously. Upon their research they have found that the earth’s magnetic field has gone through worse situations.

The Northern Lights

The Northern Lights are a wonder that occur over northern Scandinavia Island, the southern tip of Greenland and continuing over northern Canada. They are geographical located 2500km, centre in the

North magnetic pole. Even though we associate the lights only in winter time, they are present all year round.

How are the Northern Lights made? Well, it all begins with the sun and a cloud of gas called, ejection. When one of these ejections, reaches earth, it automatically collides with the magnetic field. Once collision happens, it causes currents of charged particles to flow to the poles of the earth. These particles are then converted into energy and mix with oxygen and nitrogen atoms to produce a marvellous light show.

References:

1.        Earth's Inconstant Magnetic Field - NASA Science. NASA Science. Retrieved February 25, 2012, from http://science.nasa.gov/science-news/science-at-nasa/2003/29dec_magneticfield/

2.        Brain, M. HowStuffWorks "Earth's Magnetic Field". HowStuffWorks "Adventure". Retrieved February 25, 2012, from http://adventure.howstuffworks.com/outdoor-activities/hiking/compass1.htm

3.        What are the northern lights?(Everyday Mysteries: Fun Science Facts from the Library of Congress). Library of Congress Home. Retrieved February 25, 2012, from http://www.loc.gov/rr/scitech/mysteries/northernlights.html

Salsabila Ahmed

February, 11, 2012

THE ENERGY BALL REPORT

 Series Circuit: An electrical circuit that provides only one path for the current to flow (4)&(5). 

 Parallel Circuit: An electrical circuit that provides several paths for the current to flow (5). 

Parallel Vs. Series

In order to understand parallel and series circuits, we must first know what a circuit is. A circuit is a closed path that allows electric current to flow. Having a circuit that can only sustain one load is impractical in our society (3). Since there are so many houses and buildings to light up, having a circuit per light is just not possible. For this reason there are series and parallel circuits. Both these circuits can carry more than one load. The major difference is that, in series the electric current only has one path to flow while in parallel it has several. Looking at the above diagram, we see that the series circuit is moving in a counter clockwise motion, this means that the current can only go in one direction. In this particular picture, there are three resistances connected to the batteries. The main drawback to series is, if there’s a breakage in one part of the wiring all the resisters will not work. Looking at the parallel, we again have three resisters but they are arranged “parallel” to one another. This allows the electric current to have more than one path to flow, so if there is a breakage in one part it won’t affect the other areas. The disadvantage to parallel circuits is that, the more loads put on, the more the current goes up. This is dangerous because, if the current is continuously increasing, at one point it can cause a fire (5).

Energy Ball

The energy ball experiment done in class is a fun way to learn about circuits. We saw that that when we touched the ball in a certain area, it lit up and made a hum sound. This is because we had created a series circuit. We as humans are conductors of electricity, this mean that under some circumstances we can transfer electric current. The human body is 60% water, but the water isn't totally pure. Infact the water has dissolved ions which allows electric current to flow, this is why the human body is a semi-conductor (6). In the class, we also made a parallel circuit, we had two energy balls and when one was not working it didn’t affect the other, because the current could take another path. However under some circumstances, humans are not conductors of electricity. Grounding, which means a connection to the earth, happens when a conductor is present to carry the electric flow. Example of an object that is a good conductor is copper (6). If a person is holding copper wiring while having the energy ball in hand, the ball will not activate because the individual is now grounded. The electric current will not go through them, but instead will go through the copper wiring and straight into the ground.  

 Energy used for science experiment. It’s educational and fun!! (1) 

Self- Reflection

Doing this report, I have come to a conclusion that I personally do not know enough about blogging or electronic learning. This is the first time that I have ever blogged and I found it hard at first, because I’m not so good at computers. But by doing more of it throughout the semester, I want to take initiative and try something new (2). I don’t know whether or not I will like blogging but I’m willing to try it because I know that in the future, electronic learning will be a part of my life.  

Another thing that I will have to work on is using my agenda more effectively. Even though I write all my work and test dates in my agenda, I think that by having personal deadlines will keep me more organized and focused (2).

References:

1.       Energy Ball. Stevespanglerscience. Retrieved February 11, 2012, from www.stevespanglerscience.com/img/cache/02268c260f8fff6f7502dd93a20e39be/WENB-250.jpg

2.       Learning Skills. GMB Services Home. Retrieved February 11, 2012, from http://www.gmbservices.ca/Jr/LearningSkills

3.       Parallel circuits - advantages, power, current, voltage and effective resistance. Radioactivity and Electricity Teaching Resources | Furry Elephant. Retrieved February 11, 2012, from http://www.furryelephant.com/content/electricity/parallel-circuits/

4.       Series circuit - definition of series circuit by the Free Online Dictionary, Thesaurus and Encyclopedia. Dictionary, Encyclopedia and Thesaurus - The Free Dictionary. Retrieved February 11, 2012, from http://www.thefreedictionary.com/series

5.       What are "series" and "parallel" circuits? : SERIES AND PARALLEL CIRCUITS. All About Circuits : Free Electric Circuits Textbooks. Retrieved February 11, 2012, from http://www.allaboutcircuits.com/vol_1/chpt_5/1.html

6.   The Ground Wire. hyperphysics. Retrieved February 11, 2012, from hyperphysics.phy-astr.gsu.edu/hbase/electric/bregnd.html