Question

Rolling friction coefficient is ____________ than journal bearing friction coefficient during starting and initial running of engine.

(a) higher

(b) lower

(c) faster

(d) none of the mentioned

I had been asked this question in my homework.

This interesting question is from Mechanical Friction topic in division Engine Friction and Lubrication of IC Engine

Answer 1

The correct answer is:

(b) lower

The rolling friction coefficient is generally lower than the journal bearing friction coefficient during the starting and initial running of an engine. This is because rolling friction involves less resistance compared to the higher friction encountered in journal bearings during startup when the oil film is still forming.