Ferromagnetism + Domain Theory + Right Hand Rule

Hey guuuise! Ingrid here, I decided to be awesome and steal Matthew's scribe job from Friday :]

Anywhoots, we had another sub, Mrs. Karras I believe, and we went over several things.
We received a booklet on Ferromagnetism and the Domain Theory of Magnetism, we were given about 15 mins to read through it and then answer the questions at the back of the book. We were also given notes on Oersted's Discovery/The Right Hand Rule.

Here are the answers to the questions from the booklet:
1) To magnetize a steel nail, you can either rub it against an already permanent magnet, or simply place it in a magnetic field. In order to lose it's magnetization, you can heat the magnet or remove it from the magnetic field (i.e. drop it).

2) In order for such an occurrence to, well- occur, the cans would have to be made out of a ferromagnetic material. Therefore, the cans are not made of aluminum because aluminum is not a ferromagnetic material, thus it would not be affected by a magnet.

3) One end of the known magnet would be attracted towards the ferromagnetic material (iron) and the other end would repel the permanent magnet.

4) The purpose of the Van Allen belt it to protect us from the Solar Wind, if it did not exist then we would be bombarded with solar radiation from the sun.


Okay, here are the notes on the Right Hand Rule(s). They were already super straightforward so I just copied it as it was.

Oersted's Discovery
Oersted showed a connection between electricity and magnetism. If a current is flowing in a straight wire, a magnetic field is created, in cocentric circles, around the wire.

First Right Hand Rule

Grasp the wire with your right hand. Keep your thumb pointed in the direction of the conventional (positive) current flow. The fingers of your hand circle the wire and point in the direction of the magnetic field.

Second Right Hand Rule

The direction of the field produced by an electromagnet can be found by using this rule.
Grasp the coil with your right hand. Curl your fingers around the loops in the direction of the conventional (positive) current flow. Your thumb points toward the N-pole of the electromagnet.

Third Right Hand Rule

The direction of the force on a current carrying wire in a magnetic field can be found using this rule.
Point the fingers of your right hand in the direction of the magnetic field. Point your thumb in the direction of the conventional (positive) current flow in the wire. The palm of your hand then faces in the direction of the force acting on the wire.

Here's a cheap diagram I drew for you guys as a guide, pls excuse the ugliness:

Next scribe... Will be Matthew?

September 25, 2008

Hey-o everyone!

Okay, here I am listening to tunes and procrastinating on my English project, all the while wondering what to write in this blog post... Sorry I can't compare to the awesome blogposts already made, I will try not to fail you all!

How about summarizing what we did today? Well, we didn't do much actually. We watched a video on the smartboard that was quite entertaining and informative. We also had to complete a worksheet while watching said video. The worksheet was pretty straightforward since the answers were easily derived from the video. (Don't worry, don't worry, I'll post the worksheet with the answers in a bit...)

The video was mainly about the reflection of light through/off of different mediums. I'd come up with some analogies for the concepts but I wouldn't be able to do the video justice. Gah! I wish I could just find the darned video.

Now here is the worksheet. I apologize for my horrid penmanship and diagrams (oh and my scanning isn't very good but oh well!) D: !!



1) Anywhoots, first we learned how to find the shortest distance light would travel between two points. This is done by drawing a B-prime (an imaginary point beyond the barrier, mirroring the actual point) and connecting it to point A. The point where point B-prime crosses the barrier is the point where point A and point B should meet, thus resulting in the shortest distance to travel. The same applies for question 2.

2) Read my lengthy paragraph above.





3) This is relatively straightfoward. We've been repeating this concept for the past... week? So yeah! The angle of incident = the angle of reflection.

4) Okay, we can compare this to a page in a book because the book's surface is rough, not smooth. If it was smooth, the light rays would reflect much like light would off of a mirror, thus we'd only be able to see the contents of the book at (a) certain angle(s). The rough surface allows the rays to be reflected at different angles which allows us to view the page from any angle. (Hopefully I explained this well enough!)

5) This is similar to the first and second question~!

Okay, since the answers for the rest of the worksheet are easily explained through the context in which it is found, I feel that I don't need to explain anymore. (Plus, I need to get crackin' on my English project D: )

All in all, the video provided new viewpoints for the concepts we are learning, making it easier to understand. I learned and relearned a couple of things. (I mean come on! I had no idea a polar bear is black with white fur :O who'da known? Hahaha!)

Alas, after the video, we corrected the worksheet and attempted to correct a previous assignment... "Refraction - Light." We only got two questions corrected so I shall leave that entirely up to the next scribe... Which just so happens to be...

Super Captain Awesome of Extreme Fantasticness!
(C'man, a pseudonym like that should've drawn attention LONG ago!)

adieu~ ♥!