This file is from Wikimedia Commons and may be used by other projects.
The description on its file description page there is shown below.
Summary
DescriptionSafety Parabola.png
English: The plot shows several projectile trajectories (blue lines) launched at different angles. The red curve is the envelope, called the "Parabola of Safety," which forms the boundary of all possible points the projectile can reach.
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
Please help improve this media file by adding it to one or more categories, so it may be associated with related media files (how?), and so that it can be more easily found.
Please notify the uploader with
{{subst:Please link images|File:Safety Parabola.png}} ~~~~
Captions
The plot shows several projectile trajectories (blue lines) launched at different angles. The red curve is the envelope, called the "Parabola of Safety," which forms the boundary of all possible points the projectile can reach.