Question

Swaying couple attains a maxima or minima when the crank angle is 45 degrees.

(a) True

(b) False

I have been asked this question in an interview for job.

This intriguing question comes from Swaying Couple in portion Balancing of Reciprocating Masses of Machine Dynamics

Answer 1

Right option is (a) True

To explain I would say: The swaying couple is maximum or minimum when the expression (cos θ +sin θ ) is maximum or minimum, differentiating it with respect to theta gives tan θ = 1

hence maximum/minimum value occurs at 45 or 225 degrees.