In the figure,two solenoids are approaching each other with speed v as shown.The induced current through the resistor R is
A)from a to b.
B)from b to a.
C)There is no induced current through the resistor.

Question

In the figure,two solenoids are approaching each other with speed v as shown.The induced current through the resistor R is 
A)from a to b. 
B)from b to a. 
C)There is no induced current through the resistor.

Quizplus · Accepted Answer

When the solenoids approach each other, the magnetic field lines around each solenoid change, inducing a current in the opposite direction in the other solenoid. This changing magnetic field also induces a current in the resistor R, from a to b, as determined by Lenz's Law. Therefore, the induced current through the resistor R is in the direction from a to b.

In the Figure,two Solenoids Are Approaching Each Other with Speed