Question

For a Hartnell governor which of the following relation regarding r₁/r₂ is true for isochronisms?

(a) (M.g + S1) ÷ (M.g + S2)

(b) (M.g + S2) ÷ (M.g + S1)

(c) S2/ S1

(d) S1/ S2

I had been asked this question in an international level competition.

This interesting question is from Isochronous Governor in section Governors of Machine Dynamics

Answer 1

Right option is (a) (M.g + S1) ÷ (M.g + S2)

To explain I would say: For isochronisms the equilibrium speed should remain constant throughout, i.e Range should be 0.

Applying that condition we have r1/r2 = (M.g + S1) ÷ (M.g + S2)