FIRST, really understand what your instructor is asking you to do; only then will you understand what your "information need" is.
Here are some basic requirements of the assignment:
This application may focus on unique anatomical adaptations of humans and/or animals, especially those adaptations that are particularly remarkable in some way, e.g., how does the length of bones and angle of muscle attachments allow some animal to be fast, graceful, strong, ...
Resources should, therefore, include these things (each resource need not include all of these things, but all of your resources should combine to provide the following):
Step One above is key to your success. Now that you know what you need you can get to work finding resources to "satisfy your information need".
Think of words and phrases relating to your topic or the concept you are researching. Think about the concept vocabulary, especially that of the first half of your physics textbook: torque, acceleration, moment of inertia, elasticity, center of rotation, etc.
When searching the library catalog, databases, or the internet, Boolean operators help you broaden or narrow your search and its results: