Three stage trajectory according to <a href="https://en.wikipedia.org/wiki/Theory_of_impetus" class="extiw" title="w:Theory of impetus">Theory of impetus</a> of <a href="https://en.wikipedia.org/wiki/Albert_of_Saxony_(philosopher)" class="extiw" title="w:Albert of Saxony (philosopher)">Albert of Saxony</a> (1316-1390).
<a href="//commons.wikimedia.org/wiki/User:Krishnavedala" title="User:Krishnavedala">Krishnavedala</a>
2012-07-04
<span class="int-own-work" lang="en">Own work</span>