and dropping the factor sin θ,

Aμ2 cos θ − G′μ + gMh = 0, or Aμ2 cos θ − CRμ + An2 = 0,

(5)

the condition for steady motion.

Solving this as a quadratic in μ, the roots μ1, μ2 are given by

μ1, μ2 = G′sec θ [1 ± √ (1 − 4A2n2cos θ) ];
2A G′2

(6)

and the minimum value of G′ = CR for real values of μ is given by

G′2= cos θ, CR2√(cos θ);
4A2n2 An

(7)