I am thinking about re-organizing the first half of my physics classes to push much of kinematics until later — maybe much later! Here is what I may go with:

*Start with vectors…displacements, forces, velocities (and for now, velocity is just a fancy word for speed)*

This would include vector addition, vector components, an intro to the essential right-triangle trig, and applications including “river crossing” and equilibrium problems (hanging signs and such).

*Next, a minimal introduction to kinematics…*

This would include a definition of average velocity, and an examination of x vs t and v vs t graphs for constant positive velocity. Then, a look at constant acceleration: its x vs t graph, its v vs t graph and the definition delta V over delta t. BUT NOTHING YET ABOUT: area under v vs t, kinematic formulas, word problems, positive vs negative velocity and acceleration…

QUESTION #1 FOR MY COLLEAGUES: Is that enough kinematics to take on Newton’s laws? Am I forgetting something?

*On to Newton’s Laws…*

It seems crazy to me how long it can take me to get to these if I do a full treatment of kinematics (and even projectiles!) before Newton’s laws. If I adopt this new arrangement, I think I can start Newton’s laws in September. This does mean that I can’t spiral F=ma problems which require kinematics to get the acceleration. But eventually I can spiral the other way: put F=ma into kinematics problems.

*On to…well, I am not sure…*

At first, I was thinking that next I would go back and finish up kinematics and projectiles. Then, on to work and energy, followed by momentum. (I know others prefer to reverse those two…I am not religious about that.)

But then I got to wondering: could kinematics and projectiles even wait until after all of this? I might have to skip the derivation of W = delta KE but that feels minor. Could kinematics and projectiles come right before circular motion? From projectiles right into circular motion feels kind of natural.

So that leads to QUESTION #2 FOR MY COLLEAGUES: If you delayed kinematics in the way I am considering, when would you go back to it?

*I don’t want to open comments on this blog (too much weird spam) so please find me on twitter *@pckeller* if you would like to chime in. Thank you!*