Solution
= Solution
At infinity the specific energy is $v^2/2$ and $l=bv$, so
$$
e=\sqrt{1+\frac{b^2v^4}{k^2}}.
$$
The angle through which the <velocity> is deflected between the incoming and outgoing asymptotes is
$$
\boxed{\chi=2\tan^{-1}\left(\frac{k}{bv^2}\right).}
$$