Question in determing the direction of induced emf?

[ehabmozart]

How to determine the direction of emf induced in an alternator without the need to look at the graph. (i.e) using Lenz's Law or Faraday's Laws of determining the direction? Consider for example the instant when B and dA are perpendicular and no flux is present?

Thanks for helping!

 

[Khashishi]

You do know Lenz's law, right? I don't know what more there is to say other than just repeating what Lenz's law again.

The direction of B doesn't matter. It is the change in B that matters, not B itself.