Hey guys, I would love help on the following questions. A response to any of these would be great.

1.) Which magnet motion past the wire will produce the greatest voltmeter indication: perpendicular, parallel, or no motion at all?

2.) An audio speaker has its cone attached to a metal slug that slides in and out of the core of an inductor. What would happen if someone were to gently tap on the cone of one of these speakers? What would the other speaker do? In terms of electromagnetism and electromagnetic induction, explain what is happening.


3.) The ignition coil of a gasoline-powered internal combustion automobile engine is an example of a transformer, although it is not powered by alternating current. (See below.) Explain how a transformer may be operated on electricity that is not AC:


Any responses (even just hints) appreciated. I want to understand these well but I also have about 2.33 hours to finish these and I don't know much about the concepts. Thanks!

 

What conclusion or have you found so far?
Max.

 

Well I understand the perpendicular would be best, not perfectly sure why.

 

I think I have 1 and 2 down. For number 3, the question is actually a copy of a question from all about circuits. Take a look at number 11. Nonetheless, I can't say I get it.

http://www.allaboutcircuits.com/worksheets/trans1.html

 

So, when is a magnetic field created in a coil of wire? What is required to maintain the field?

 

1.) Parallel motion will because current is always perpendicular to the magnetic field.


2.) If Speaker 1, is tapped, Speaker 2 would create noise. Electric currents create an electric field. An electric field creates current when it’s in motion. When you tap the speaker, you are moving the magnet of speaker one, which creates a current and moves the magnet of Speaker 2. Therefore, Speaker 2 creates a noise too.

OK, I wrote answers to 1 and 2, your reactions are appreciated.

 

So, when is a magnetic field created in a coil of wire? What is required to maintain the field?

A magnetic field is created when electricity runs through the wire. Right? And in order to maintain it you have to keep a current running.

 

Your description of Problem #2 if very vague. You say that AN audio speaker is connected to a metal (not necessarily a magnet and not necessarily magnetic) slug in an inductor. But then you go talking about another speaker without describing how the speakers are connected.

 

Well I understand the perpendicular would be best, not perfectly sure why.

So how can you say you understand it if you don't know why?

Is this just a straight piece of wire?

How can a magnetic field be used to produce a voltage in a wire? Hint: Think of Physics II and Maxwell's Equations.