Multiple Choice
As shown in the figure,a wire and a 10-Ω resistor are used to form a circuit in the shape of a square with dimensions 20 cm by 20 cm.A uniform but non-steady magnetic field is directed into the plane of the circuit.The magnitude of the magnetic field is steadily decreased from 2.70 T to 0.90 T in a time interval of 96 ms.What is the induced current in the circuit,and what is its direction through the resistor?
A) 75 mA,from b to a
B) 45 mA,from b to a
C) 75 mA,from a to b
D) 45 mA,from a to b
E) 110 mA,from a to b
Correct Answer:

Verified
Correct Answer:
Verified
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