Friction can be reduced by changing from:
ASliding to rolling
BRolling to sliding
CPotential to kinetic energy
DDynamic to static motion
Answer & Solution
Correct answer: A. Sliding to rolling
1. Sliding (kinetic) friction is generally larger than rolling friction.
2. Replacing a sliding contact with rolling contact (as in ball bearings) lowers friction.
3. Therefore changing from sliding to rolling reduces friction.
_Source: RRB Group D (RRC) PYQ, held 27-10-2013, Q.23._
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