Chapter 21, Problem 14Q

To determine

To Explain:force is required to pull out aluminium sheet held between poles of large bar magnet.

Explanation of Solution

Introduction:

Whenever there is magnetic flux linked with a coil varies, an emf is induced which in turn generates current.

A force is required to pull out aluminium sheet from the magnetic field because area of the linked with sheet changes in turn changing the magnetic flux.

This varying flux will induce currents in “free”conduction electrons of the aluminium to oppose the change. Magnetic field would work on the eddy currents and the subsequent force would oppose the motion of aluminium sheet.

Conclusion: Therefore, some amount of force is required to take away the sheet from between the poles.