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My textbook (NCERT Physics Class 12th) has the following figure (Pg 212).

enter image description here

The Arm PQ is moved to the left side thus decreasing the area of the rectangular loop. This results in a decrease in magnetic flux in the Downward (inside the page) direction. Hence, according to lenz's law, the induced current should be in Clockwise direction but the book says the opposite.

Am I missing something? or is the book wrong?

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To me it seems that the book is indeed wrong. –  Joe Jan 31 '13 at 8:10
Yes, it's wrong. It's enough to see that the current pictured would induce a magnetic field directed outward, which would increase the variation of B in a positive feedback. Which is against the reason for which the "Lenz's minus" was introduced. –  Bzazz Jan 31 '13 at 10:55

1 Answer 1

I think the X's represent magnetic field going out of the page. If this is true, than the current will indeed be in the counter-clockwise direction, as the book says.

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No, X'es represent the field going inside the page. –  Aneesh Dogra Feb 3 '13 at 9:11

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