Now the switch on the electromagnet is reopened. the magnitude of the external magnetic flux through the wire loop (a. increases, b. decreases, c. remains constant), and there is (a. zero, b. a clockwise, c. a counterclockwise) current induced in the loop (as seen from the left.

Answers:
Blank 1: Option (b) decreases
Blank 2: Option (b) clockwise 

Explanation:
Blank 1: The answer to the first blank is pretty straightforward that the external magnetic flux through the wire decreases because the electromagnet is reopened. As, after reopening the electromagnet, there will no external magnetic field, hence external magnetic flux would decrease.

Blank 2: According to Lenz’s law, "The current induced in the wire loop opposes the change in the external magnetic flux that caused the current." Therefore, if the external flux has disappeared (as electromagnet is reopened), the induced current should now be opposite to what it was when the field was present. Usually the current is in counterclockwise direction; hence, after electromagnet is reopened, the current would be in opposite direction to counterclockwise direction. Therefore, the correct answer is clockwise direction.

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