Motors and Generators (1 Viewer)

[Dash]

I have a question here that is not outlined in the books.
Well, I was alright with the concept of generators until I came to this link below. Now, I asked sum ppl what the hell was up with the direction of the induced currents, but I didn't find any supporting material in the text. Can someone explain to me why the induced current is travelling in the direction that it is? Shouldn't the current travel in the opposite direction that it is because of the direction the coil is forced to rotate in?

http://www.walter-fendt.de/ph11e/generator_e.htm

 

[BlackJack]

(edited.) It's simply a moving conductor in a magnetic field.
As you watch, the wire moving left in the downwards field generates a force outwards on the charges inside. Hence the current is as it is.

 

[Dash]

But if its not an application of Lenz's Law, then I'm so lost... explain plz!

 

[Rahul]

Originally posted by BlackJack
This isn't Lenz's Law in action because it isn't a changing magnetic field. It's simply a moving conductor in a magnetic field.

umm....it is an application of lenz's law. the changing magnetic field comes when the conductor cuts it as it is rotates. the magnetic field is always 'there' and it changes, relative to the motion of the conductor.
this is the whole principle of generators, no?

 

[Dash]

Argh. This is taking me too long. Rahul, come online!

 

[+:: $i[Q]u3 ::+]

i'm not rahul but i hope this is okay

it IS lenz's law

remember lenz's law - the current will be induced to OPPOSE the change in flux
ie to OPPOSE the movement of the coil.

use right-hand rule with a force acting AGAINST the coil's motion.
that's induced current.

 

[Rahul]

lol. BJ, its the old age mate.

 

[BlackJack]

Lol, at last count I seemed to be 1343 or thereabouts.

So it is, I apologise for the confusion. Just remembered almost everything's Lenz's law really.

 

[mazza_728]

i found the same problem wit this can anyone explain in laymens terms?

 

[Dash]

In a generator, current is induced in the wire in such a way that it will oppose the motion of the rotating coil.
As mentioned above, it's an application of Lenz's Law