e.g., the forces of cohesion that hold the skateboard together, which is why you cannot make a skateboard of jello.

i.e., graphical or analytical methods

or the skateboarders' demonstration

I.e., non-quantum

Non-relativistic, v << c.

A short paragraph to describe a very complex controversy! The paragraph is acceptable, but does not do it justice. Well worth reading about, e.g., Galileo's Daughter, by Dava Sobel (UCF Main Library General Collection - 4th Floor QB36.G2 S65 1999 Available)

This is the ordinary assumption in elementary physics. Air flow properties are very difficult to model, so we ignore them. This is the same as saying to our speeds are not large enough to draw appreciable drag from the air, so they can be ignored... until you need high precision!

Sneak preview on syllabus is related to this analysis. Study both.

ooops should be Ry^2

Lovely diagram

The angles here are not that helpful. Main thing is to build resultant from four components Ax, Ay, Bx, By, then get the trig on the resultant R

Huge. Fig. 2 is one to keep in mind all of the semester.

Very important

Excellent sentence about analysis of a ballistic trajectory

This is known as "adding in quadrature" -- i.e., add the squares of each perpendicular side.

Oh, no! Nothing could be further from the truth! But we can provisionally accept this statement for the moment.