In the figure,a C-shaped conductor is in a uniform magnetic field B,which is increasing.The polarity of the induced emf in terminals X and Y is
A) X and Y are at the same potential.
B) X is positive and Y is negative.
C) X is negative and Y is positive.

Question

In the figure,a C-shaped conductor is in a uniform magnetic field B,which is increasing.The polarity of the induced emf in terminals X and Y is 
A) X and Y are at the same potential. 
B) X is positive and Y is negative. 
C) X is negative and Y is positive.

Quizplus · Accepted Answer

According to Faraday's Law of Induction, a changing magnetic field induces an emf in a conductor. In this case, the magnetic field is increasing, which means there will be an induced emf in the conductor. The direction of the induced emf can be determined using Lenz's Law, which states that the induced emf will create a magnetic field that opposes the original changing magnetic field. Since the magnetic field is increasing, the induced emf will create a magnetic field in the opposite direction. By applying the right-hand rule for current, we see that the induced current flows clockwise from X to Y, which means that X will be negative and Y will be positive. Therefore, the correct choice is C.

In the Figure,a C-Shaped Conductor Is in a Uniform Magnetic