What is Electromagnetic Induction and How Does it Work?

[gabby_w]

Hi everyone,
So I feel sort of stupid posting what you'll probably find is a very elementary question but physics really isn't my best subject and I'm completely stumped. Thanks so much!
Oh, and there's also the possibility that this question is just really badly worded.

Homework Statement

Homework Equations

It's a question based simply on theory, not really any equations involved that could help with the answer I don't think..

The Attempt at a Solution

I was unaware that you could induce a current in a coil without a magnet... So I have no solutions?

 

[SammyS]

The coil on the left produces a magnetic field, when current flows through it.

 

[gabby_w]

Yeah I felt sort of stupid after I posted this question and figured that out... But with part (a) of the question, closing the switch wouldn't cause a current to flow through it, right? And therefore no magnetic field? Because it doesn't say that the power source is on until part (b)...

 

[SammyS]

Yeah I felt sort of stupid after I posted this question and figured that out... But with part (a) of the question, closing the switch wouldn't cause a current to flow through it, right? And therefore no magnetic field? Because it doesn't say that the power source is on until part (b)...

That's precisely when the circuit on the left has most influence on the circuit on the right.

Closing the switch means that the circuit on the left suddenly produces a magnetic field through the coil in the circuit on the right. However, according to Lenz's Law, a current is induced in the circuit on the right in a direction which produces a magnetic in a direction which tends to oppose any change in magnetic field through the coil.