This video starts with a simple acceleration problem and then addresses a commonly held misconception that a negative acceleration always means you are slowing down. I do this by way of examples. Kate (my wife) drove the Prius with a camera suction cupped to the window and videoed me riding my bike several times. In the end I ended up with four different examples on the screen at once and 25 different video layers to describe it all. I am really proud about how well it worked. Enjoy.
0:26 Reading the problem
0:40 Seeing the problem
1:14 Translating the words to Physics
1:54 Solving the problem
3:50 Why is the number on the bike positive?
4:48 How can the bike be speeding up if the acceleration is negative?
5:50 Comparing velocity and acceleration directions
7:28 All four bike examples on the screen at the same time
7:53 Why isn't there a direction on our answer?
8:51 Outtakes or how the bike riding was filmed
[url="http://www.flippingphysics.com/walking-position-velocity-and-acceleration-as-a-function-of-time-graphs.html"]Walking Position, Velocity and Acceleration as a Function of Time Graphs[/url]
[url="http://www.flippingphysics.com/introduction-to-acceleration-with-prius-brake-slamming-example-problem.html"]Introduction to Acceleration with Prius Brake Slamming Example Problem[/url]