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good morning class let's go to your natural science book okay and let's carry on with unit 6

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in this unit remember we have been talking about magnetism yes and how can we identify

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metallic and non-metallic devices, okay? So, in our first... in the first page...

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In the first page, remember we talked about permanent magnets, okay?

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That are permanent and can be man-made. Induced magnet or temporary magnets, okay?

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that give a magnetic force for a period of time or natural magnets okay like the

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magnet it remember we copy this in your book and you choose different examples

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to copy in your notebook right we talked about the magnetic force the other day

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what was a magnetic field okay although it is invisible no this area is where

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the magnetic force work and today we are going to talk about the poles okay the magnetic poles of a

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magnet okay so remember in all magnetic objects the moving charge begin and end at the magnetic

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poles there are two poles the north pole and the south pole okay look at this photograph that i

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have about this look ends and start okay in the north and in the south creating a

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magnetic field okay what else we have to know about this okay so we have to know

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that the poles

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are where the magnetics

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are.

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If you put any two magnets

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together, there are two things

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that can happen.

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One, each pole is attracted

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to a pole with the opposite charge.

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The magnets come together

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because the opposite poles

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attract each other.

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Two, the magnets

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push each other away

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because identical poles

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repel each other.

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okay so positive negative are going to attract negative positive are going to

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attract when the magnets are the same pose they are going to repel look at

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this sad face okay if you put any two magnet

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north north will repel south south will repel and the magnetic field

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which is going to go away let's see we have learned that magnets can be

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temporary or permanent but how can we distinguish a true magnet from a

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magnetic material how can we distinguish a true magnet from a magnetic material

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okay we have to see if the magnets attract to another one okay if it

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doesn't magnet okay this mean is not a magnet itself gold and silver for

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example are not not magnetic