Question

In the figure, a conducting ring of certain resistance is falling towards a current carrying straight long conductor. The ring and conductor are in the same plane. Then the

• A. induced electric current is zero
• B. induced electric current is anticlockwise
• C. induced electric current is clockwise
• D. ring will come to rest

Answer 1

The Correct Option is C

As the conducting ring falls closer to the current-carrying conductor, the magnetic field experienced by the ring increases. The magnetic field B due to a long straight conductor carrying current is circular and its magnitude decreases with distance from the wire. When the ring falls, it experiences an increasing magnetic flux. According to Lenz’s Law, the induced current in the ring will oppose the change in magnetic flux. Since the flux is increasing into the page (based on the right-hand rule and current direction in the conductor), the ring will induce a current that creates a magnetic field out of the page (to oppose the increase). Using the right-hand thumb rule, the induced current must be in the **clockwise direction** to produce a magnetic field out of the page.
Thus, the solution is (3) induced electric current is clockwise.