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2.2.1 (1 Viewer)

kimmeh

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outline Michael Faraday's discovery of the generation of an electric current by a moving magnet

can someone please elaborate on this? :p i know that an emf is induced when a magnetic field is changing.
 

Xayma

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Basically using a needle in a wire coil which was in essence a circuit. Faraday noticed that as a magnet was brought near a circuit the needle went to one direction. If the magnet was left there the needle did not move, but when it moved back the needle again moved but pointed in the other direction.

This was due to the free electrons in the wire being moved under a magnetic field as they have a negative charge as the magnet is moved back the forth the electrons move back and forth creating a current (AC current)
 

Xayma

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Isnt much information on how he discovered it available.

Basically he set up a coiled metal wire with a needle in a middle. As he moved a magnet he noticied that the needle became magnetised and pointed opposite the directions were moving.

When the magnet wasnt moving the needle wasnt magnetised.

As he moved it away he noticed that it again became magnetised and pointed the other way.

Hopefully that satisfies the verb stupid "Outline"
 

Dash

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Faradayz Discovery:
The EMF induced in a conductor is directly proportional to the rate at which the conductor cuts though the magnetic field lines.
In other words, the faster you move the magnet relative to the coil, the amount of EMF induced is increased proportionally...
 
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+:: $i[Q]u3 ::+

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faraday discovered the generation of an electric current...

imagine a solenoid set up in a circuit with a galvanometer of some sort. faraday moved magnets near the solenoid, and found that when the magnet was in relative motion, the galvanometer deflected ie a current was generated. he also found that when the magnet was moved in the opposite direction, the galvanometer needle deflection was also in the opposite direction. i.e. the direction of hte current depended on the direction of motion. Also he found that the amount of deflection was dependent on how fast the magnet was moving with respect to the coil.
 

Ragerunner

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HEHEHE Just you wait till you get to the NEXT core topic. HEHEHE

Nah just kidding, I'm not scaring you, AM I??
 

lil_star

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simply:

- take a solenoid
- connect it to an ammeter
-take a magnet's (north pole towards the solenoid)
- observe on the ammeter

North pole towards the solenoid=
using the right hand grip rule....the movement of the magnet towards the solenoid will create a change in magnetic field, giving rise to a change in flux (a noth pole will be set up to oppose the change in magnetic field caused by the pole moveing towards the solenoid), this change in flux will give rise to an induced current which will flow in order to oppose the change which caused it (lenz's law) ie the current will flow anticlockwise (looking from the side magnet is moved from)

see the pic:
faradays law.jpg at the bottom of my post.

similarly for a north pole moving away the solenid will induce a field which will oppose the moving magnet....ie a south pole will be induced in the solenoid.....using right hand grip rule the current will flow in a clockwise direction...

hope this helps...i know its a bit confusing...but soon ud know it sooo well...same happened with me! btw my drawing is not so good...bear with it!
 
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+:: $i[Q]u3 ::+

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Originally posted by kimmeh
this must be the WORST module out of all of physics... i absolutely hate it.
hehe... no way... =)
it'll get better =)
 

elizabethy

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this was my worst module!!:mad: :mad: thank god , i never have to do it again!!!!!:D :D
 

gbong

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im doing dis module now and it realli sucks!!! >.< compared to space dis does not make any sense wat so eva....
 

Ragerunner

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At least this module is more practical in real life!

Stupid space and relativity, as if we'd ever travel at the speed of light.......
 

Ragerunner

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Don't scare them!

Don't tell them that they got to learn crazy stuff like how solar cells works in terms of electron movement and all the crazy mathematics involved calculating the threshold frequency of a lightsource required to displace electrons from a substance.

Your scaring them "..." !! Stop it!!
 

lil_star

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Originally posted by Ragerunner
At least this module is more practical in real life!

Stupid space and relativity, as if we'd ever travel at the speed of light.......

relativity was *okay* but i hated the graphs in space.....i cud nevr believe that relativity was true :-s

i liked motors n gen as u can imagine whats happening more easily!
 

Xayma

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Originally posted by Ragerunner
Stupid space and relativity, as if we'd ever travel at the speed of light.......
Maybe not near it, but everyone knows after the 3rd World War, Cochran will travel in the pheonix past the speed of light, leading to the Vulcans who were studying nearby noticing the warp signature and coming to the Earth.
 

BlackJack

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:haha:
where has this thread gone?
---
more seriously, what has bos done to physics?
I'm sure motors and gnerators has to be logical... or the dot point mix 'n' match has gone too far.
 

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