What is the direction of current flow in coil X when placed near coil Y?

[anonymousZ10]

1. Homework Statement
Based on what I've got, i guess the answer is A. However, I'm not quite sure of myself.
From what I can see coil Y has its own magnetic field because current is flowing in that coil. When there's a flow of current there will be a magnetic field around it. Thus, placing coil Y close to coil X will produce induced e.m.f on coil X.

The main problem here is how to determine the direction of current flow in coil X ?

well, please correct me if my theory was incorrect

Homework Equations

The Attempt at a Solution

 

[BvU]

Hi Z,

You are searching in the right direction and now need something to go by: an equation perhaps ? Could you post the most relevant ?
What determines the induced emf ? And its polarity ?

 

[anonymousZ10]

Hi Z,

You are searching in the right direction and now need something to go by: an equation perhaps ? Could you post the most relevant ?
What determines the induced emf ? And its polarity ?

i've checked the answer just now, guess what, the right answer is B :D
Would you care to help me find the reason why is this
I just don't get it

 

[BvU]

Well, I tried to help in post #2. THe questions still stand!

Approaching from the other end: what happens when the switch is opened ?

 

[anonymousZ10]

Well, I tried to help in post #2. THe questions still stand!

Approaching from the other end: what happens when the switch is opened ?

I'm still trying to figure out what happens when the switch is opened. lol

 

[BvU]

Well, you already said it in so many words:

From what I can see coil Y has its own magnetic field because current is flowing in that coil. When there's a flow of current there will be a magnetic field around it.

and what happens to current when that switch opens ?

Oh, the questions from post # 2 Are still open !