In a locomotive, the ratio of the connecting rod length to the crank radius is kept very large in order to
(a) minimize the effect of primary forces
(b) minimize the effect of secondary forces
(c) have perfect balancing
(d) start the locomotive conveniently
The question was posed to me in an interview.
This interesting question is from Balancing of Several Masses Rotating in Different Planes topic in portion Balancing of Rotating Masses of Machine Dynamics