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4.2 friction — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysics4.2 friction1 Mark
MCQ
Which is a suitable method to decrease friction
  • A
    Ball and bearings
  • B
    Lubrication
  • C
    Polishing
  • ✓
    All the above
✓

Answer

Correct option: D.
All the above
d
(d)Ball and bearing produce rolling motion for which force of friction is low. Lubrication and polishing reduce roughness of surface.

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