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Use Lenz's law to determine the directio...

Use Lenz's law to determine the direction of induced current in the situations described by figure.
(a) A wire of irregular shape turning into a circular shape,
(b) A circular loop being deformed into a narrow straight wire.

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(a) As per the statement when given loop changes its shape from irregular to circular inward magnetic flux linked with it will increase. (because of increase in area). Hence according to Lenz.s law, induced current should flow in such a direction which can decrease the inward magnetic flux. For this, induced current should flow anticlockwise. i.e. in a direction `a to d to c to b to a to d to c` in the given loop.
(b) As the loop contracts, outward magnetic flux linked with it will decrease. Hence according to Lenz.s law, induced current should flow in such a direction which can increase outward magnetic flux. For this, induced current should flow clockwise i.e. in a direction `a. to b. to c. to d. to a.` in the given loop.
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KUMAR PRAKASHAN-ELECTROMAGNETIC INDUCTION-Section B (Numerical) Numerical From Textual Exercise
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