The Commander Andrew Coley, Darryl Bell, James Farmer, Lane Dukart

Well-Oiled Machine

Design Overview Our team used a plastic box without a lid as a frame. We cut beer boxes into strips and duct taped them onto the inside walls of the box, creating a series of ramps that spiral towards the bottom of the box. In the corner where the track reaches the bottom of the box, we cut a hole so that the ball shoots out of the box into a dead end, where it stops after 15 seconds.

Stored Energy The ping pong ball starts with gravitational potential energy (mgh). When the ball is released it forms kinetic energy (½ mv²). The ball loses energy on its way down the track due to friction. When the ball hits a corner, if it comes completely to a stop it starts these three steps all over again.

Design/Construction Problems Slope too fast = not enough height to go for 15 seconds and ball not in control. Slope too slow = getting stuck on the track. Started taping at the top, harder to tape once we got to the bottom. Ending time depends on force of start push. Conversion in corners, needed a few ramps.

Conclusions The ball reaches the end of the track in approximately 15 seconds and the roller coaster meets all of the requirements. The ball goes faster as it gets closer to the bottom, due to increased slope and momentum. Going simple made this easy.