Help with the basics of this topic (1 Viewer)

[mymuse]

I've almost finished the topic in school, and i understand how bits and pieces work, but nothing really completely makes sense to me.

From the 'why do people think this topic is so hard' thread, someone suggested that everything revolves around lenz's law and faraday's law (and text book explanations haven't really helped), so i was wondering whether someone wouldn't mind explaining these two?

thanks in advance.

 

[me121]

well, a motor, and a generator are just applications of faraday's law. Lenz's law is also in the syllabus a bit with it's applications and theory. I could give you an explanation, but i would just be repeating what i've said in my book on the relevant pages, you can get a copy from here, then click on HSC Physics Syllabus Notes 2007.

Btw, your profile says your HSC was in 2003, is that correct?

 

[mymuse]

thankyou andrew harvey. your notes are brilliant.

as for my profile, i seem to have registered with the year i started year 7, which is really weird. but it's all fixed now.

 

[me121]

thankyou andrew harvey. your notes are brilliant.

as for my profile, i seem to have registered with the year i started year 7, which is really weird. but it's all fixed now.

no worries...

 

[mymuse]

i have a question about ac induction motors;

since alot of books ahve been describing it as a squirrel cage, and it consists only of a stator and a rotor, does it mean that when it operates, there are two concentric cylinders that are spinning in opposite directions (due to Lenz's law)?
i'm having trouble visualising it.

 

[me121]

i have a question about ac induction motors;

since alot of books ahve been describing it as a squirrel cage, and it consists only of a stator and a rotor, does it mean that when it operates, there are two concentric cylinders that are spinning in opposite directions (due to Lenz's law)?
i'm having trouble visualising it.

Here is the thing. The syllabus does not require you to know how an AC induction motor works. You do however need to, "1. perform an investigation to demonstrate the principle of an AC induction motor". "1. describe the main features of an AC electric motor". So for the latter point, you can describe an induction motor, however you can just describe a simple AC motor.

However, I cannot answer your specific question, because I'm not sure. Sorry.

 

[mymuse]

Here is the thing. The syllabus does not require you to know how an AC induction motor works. You do however need to, "1. perform an investigation to demonstrate the principle of an AC induction motor". "1. describe the main features of an AC electric motor". So for the latter point, you can describe an induction motor, however you can just describe a simple AC motor.

However, I cannot answer your specific question, because I'm not sure. Sorry.

okay thanks.
it's ok, if i can avoid learning about it, i won't bother, exam's coming up soon.

 

[mymuse]

and also,

i've read so many ambiguous texts, so i need someone to verify for me, AC motors and generators are exactly the same, and DC motors and generators are exactly the same?

 

[me121]

and also,

i've read so many ambiguous texts, so i need someone to verify for me, AC motors and generators are exactly the same, and DC motors and generators are exactly the same?

Yes you can get ones that are exactly the same. However there are different types of motor's and generators and only the simple motor and generator have the same structure.

 

[mymuse]

Yes you can get ones that are exactly the same. However there are different types of motor's and generators and only the simple motor and generator have the same structure.

ok