### RipStik for vector exposition and addition

Vectors are fun. I sat in the computer laboratory staring at section 8.3 of Larson's Algebra and Trigonometry text. Nothing I saw on the page looked like fun. My mind wandered to my RipStik. And then in a flash I knew I wanted to fling a ball at a right angle from a moving RipStik and use the radar gun to get the ball launch speed. The RipStik could be timed across a distance with a stopwatch.

Kenneth used the radar gun to obtain the ball launch speed.

Marla timed the RipStik over an 800 cm distance. She obtained a time of 3.28 seconds for a
RipStik velocity of 243.9 cm/s.

Maggie handled the RipStik riding and ball launching, freeing me up to photo-document the experiment.

Lecture then proceeded on the sidewalk. Note that the radar gun measured in kilometers per hour. 31 kph was 861 cm/s. The ball was thrown perpendicular to the path of the RipStik directly at the radra gun, but the path over the ground, and the net velocity vector, carried the ball towards the Araucaria pine. The i, j notation is upside down so that it would be right side up for the students who had settled onto the faculty building stairs.

The class then returned to the classroom to provide some definitions for magnitude, direction angle, and the unit vectors.

The day before I sneaked a couple vectors onto the board when covering a trajectory equation in section 7.3.

Vectors are fun, especially when is able to play with them outside!