In a central force field, the trajectory of a particle of mass m and angular momentum L in plane polar coordinates is given by: \(\frac{1}{r} = \frac{m}{L^2}(1 + ϵ \cos \theta)\)
where ϵ is the eccentricity of the particle's motion. Which one of the following choices for ϵ gives rise to a parabolic trajectory?
1
ϵ = 0
2
ϵ = 1
3
0 < ϵ < 1
4
ϵ > 1