(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

See figure attached.

2. Relevant equations

3. The attempt at a solution

If we attempt to solve part a) in this question we encounter several confusions.

If we assume i(t) to be a positive current, the magnetic flux will flow through the core in a counter clockwise direction.

How are we supposed to deduce the direction of the induced voltage,

[tex]e_{ind}[/tex]

?

If you tell me whether or not i(t) is increasing or decreasing or remaning constant I can then tell you how eind relates to v.

Are we just supposed to assume it is either increasing or decreasing? If so, the relation to v to eind will have a sign difference in each case.

Assume i(t) is increasing,

[tex]e_{ind} = -v = -\frac{d\psi}{dt}[/tex]

Assume i(t) is decreasing,

[tex]e_{ind} = v = -\frac{d\psi}{dt}[/tex]

As you can, depending on which case I assume, my expression of v will change by a negative sign.

This will affect the answer in part b).

How do we know which one to choose?

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# Homework Help: Direction of Induced EMF (Faradays Law) Confusion

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