A coil lies flat on a tabletop in a region where the $\vec { B }$ field vector points straight up.The magnetic field vanishes suddenly.When viewed from above,what is the sense of the induced current in this coil as the field fades?
A)The induced current flows counterclockwise.
B)The induced current flows clockwise.
C)There is no induced current in this coil.
D)The current flows clockwise initially, and then it flows counterclockwise before stopping.

Question

Quizplus · Accepted Answer

According to Faraday's law of electromagnetic induction, a changing magnetic field will induce an electromotive force (EMF) in a closed loop of wire, which in turn will cause an induced current to flow through the loop. The direction of the induced current can be determined using Lenz's law, which states that the direction of the induced current will be such that it opposes the change in magnetic flux that produced it.

In this scenario, the magnetic field suddenly vanishes, which means that the magnetic flux through the coil is decreasing. To oppose this decrease in flux, the induced current in the coil must produce a magnetic field that points in the opposite direction. By using the right-hand rule for determining the direction of the magnetic field around a current-carrying wire, we can conclude that the induced current must flow counterclockwise when viewed from above. Therefore, the best choice is A) The induced current flows counterclockwise.

A Coil Lies Flat on a Tabletop in a Region B⃗\vec { B }B

A Coil Lies Flat on a Tabletop in a Region $\vec { B }$