Question

A metal sheet is placed in front of a strong magnetic pole. A force is needed to
(a) hold the sheet there if the metal is magnetic
(b) hold the sheet there if the metal is nonmagnetic
(c) move the sheet away from the pole with uniform velocity if the metal is magnetic
(d) move the sheet away from the pole with uniform velocity if the metal is nonmagnetic.
Neglect any effect of paramagnetism, diamagnetism and gravity.

Answer 1

Movement Increases Eddy Current

Explanation:

(a) hold the sheet there if the metal is magnetic

(c) move the sheet away from the pole with uniform velocity if the metal is magnetic

(d) move the sheet away from the pole with uniform velocity if the metal is nonmagnetic

• The solid attractive post will pull in the magnet, so a power is expected to hold the sheet there if the metal is attractive.  
• In the event that we move the metal sheet (attractive or nonmagnetic) away from the post, whirlpool flows are instigated in the sheet.  
• In light of vortex flows, warm vitality is created in it.  
• This vitality comes at the expense of the motor vitality of the plate; along these lines, the plate backs off.  

Along these lines, a power is expected to move the sheet away from the shaft with uniform speed.