Join thousands of students who trust us to help them ace their exams!Watch the first video
Multiple Choice
An outer ring is connected to a variable voltage source. If the battery's voltage is continuously INCREASING, what is the direction of the induced current in the inner ring, centered inside of the outer ring?
A
Clockwise
B
Counterclockwise
C
Into the page
D
Out of the page
Verified step by step guidance
1
Identify that the problem involves electromagnetic induction, specifically the concept of Lenz's Law, which states that the direction of the induced current will oppose the change in magnetic flux that produced it.
Recognize that the increasing voltage in the outer ring will increase the current flowing through it, thereby increasing the magnetic field it produces. According to the right-hand rule, if the current in the outer ring is flowing clockwise, the magnetic field will point into the page at the center of the ring.
Determine that as the magnetic field through the inner ring increases into the page, the inner ring will experience a change in magnetic flux.
Apply Lenz's Law: The induced current in the inner ring will flow in a direction that opposes the increase in magnetic flux. Therefore, the induced magnetic field must point out of the page to counteract the increasing field into the page.
Use the right-hand rule again to find the direction of the induced current in the inner ring. For the induced magnetic field to point out of the page, the induced current must flow counterclockwise in the inner ring.