The disc of an instrument using eddy current damping should be of
The disc of an instrument using eddy current damping should be of
1). Conducting and magnetic material
2). Non-conducting and magnetic material
3). Conducting and non-magnetic material
4). None of the above
2 answers
Eddy current damping:
- When a conductor moves in a magnetic field an emf is induced in it and if a closed path is provided, a current (known as eddy current) flows
- This current interacts with the magnetic field to produce an electromagnet torque which opposes the motion
- This torque is proportional to the strength of the magnetic field and the current produced
There are two common forms of damping devices:
1) A metal former which carries the working coil of the instrument
2) A thin aluminium disc attached to the moving system of the instrument, this disc moves in the field of a permanent magnet; The disc should be of conducting and non-magnetic materialOther Questions
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