Quick Flyback Convertor Question

[crystalbrite]

In a flyback convertor, why does the polarity of v2 on the secondary winding change compared to a normal transformer circuit as shown in the picture attached?

If the voltage and current, v1 and I1 in the primary winding are flowing in the same direction in both circuits shouldn't the polarity of the induced voltage and current v2 and I2 be the same polarity in both circuits?

 

[crystalbrite]

Is the direction of the voltage and current in the secondary just due to the way the wire has been wrapped around the transformer core as I have drawn in the picture attached?

 

[sophiecentaur]

Is the direction of the voltage and current in the secondary just due to the way the wire has been wrapped around the transformer core as I have drawn in the picture attached?

The sense of the secondary current would be different for different connections but the effect on the primary ('back emf') would be the same in each case.