Solution
= Solution
The orbit is \b[unbound for $\boxed{k\ge\sqrt2}$]: parabolic at equality and hyperbolic above it. The pericentre speed has reached or exceeded the local <escape velocity>.
= Solution
The orbit is \b[unbound for $\boxed{k\ge\sqrt2}$]: parabolic at equality and hyperbolic above it. The pericentre speed has reached or exceeded the local <escape velocity>.