max deformation is not at when \(\theta=90^o\) because \(F=0\) as \(cos(90^o)=0\). In fact distortion at \(\theta=90^o\) is zero.
When \(\theta\approx 0\),
\(F\) is around its maximum value is the distortion most pronounced.
What happen when \(\theta=0\)? \(F\) as the result of \(\omega\times v\) is still perpendicular to both \(\omega\) and \(v\), but symmetry dictates that \(F\) rotates in the plane containing the spin, perpendicular to the direction of travel. Since in all orientations \(F\) acts against the centripetal force, the particle spin is reduced. The particle spins slower but is not distorted.
