In hard-disk drives, ferrofluids are used as:

  1. the power supply
  2. the display
  3. data storage
  4. seals that keep dust out around rotating shafts
Answer

D) seals that keep dust out around rotating shafts

Liquid seals held by magnets. SLO P-09-E-09 · Understanding

Physics MCQ · More Magnetism and Electromagnetic Induction MCQs · Practise