This item is an applet-based problem for introductory physics on the topic of inertia in motion. A hockey puck moving on a frictionless air hockey table is given a momentary push in the +y direction. What is the motion of the puck after the push? The user chooses from four animations that represent possible results. Physlet-based problems are intended to probe student understanding, elicit misconceptions, and serve as a springboard for discussion. Electronic student response systems (clickers) are often used to allow anonymous "voting" on the correct answer.