The core of a transformer is laminated so that

Eddy currents are used in

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: $A$ bar magnet dropped through a metallic cylindrical pipe takes more time to come down compared to a non-magnetic bar with same geometry and mass.
Reason $R$: For the magnetic bar,Eddy currents are produced in the metallic pipe which oppose the motion of the magnetic bar.
In the light of the above statements,choose the correct answer from the options given below:

The shiny metal disk in the electric power meter (analog type) rotates due to

The small energy losses in transformers due to eddy currents can be reduced by

$A$ magnet is dropped down an infinitely long vertical copper tube. Then