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The current flows from A to B in a straight wire as shown in the figure, and it is decreasing with time. The induced current in the loop placed near it .........

Asked in RS Academy GUJCET booklet · Direction of the induced current

Figure: Direction of the induced current
Answer: (2) In anticlockwise direction

Step-by-step solution

Setup (figure): the current flows from A to B, left to right, along a straight wire; the loop lies in the same plane, above the wire.

Field of the wire at the loop: by the right-hand thumb rule, above a left-to-right current the field points out of the page.

The current is decreasing, so this outward flux through the loop is decreasing.

Lenz's law: the induced current opposes the change, so inside the loop it must produce an outward field to make up the loss.

A current whose field points out of the page, towards the viewer, circulates anticlockwise as seen by the viewer.

So the induced current in the loop is anticlockwise.

Why the other options are wrong

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