Magnetism and Electromagnetism
The left hand rule correlates to

Current, induced e.m.f. and direction of force on a conductor
Current, magnetic field and direction of force on a conductor
Self induction, mutual induction and direction of force on a conductor
Magnetic field, electric field and direction of force on a conductor

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Magnetism and Electromagnetism
Main causes of noisy solenoid are

Both of the listed here
uneven bearing surface, caused by dirt or uneven wear between moving and stationary parts
None of these
strong tendency of fan out of laminations at the end caused by repulsion among magnetic lines of force

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