This is one of set of applets designed to be a problem posing playground for teachers.[br][br]The left hand panel shows the trajectory in space traced out by a moving object. [br][br]The right hand panel shows the horizontal and vertical motions of that object as functions of time.[br][br]The user can control - [br] - the number of intervals during which the object moves with constant speed (links slider)[br] - the times at which the speed of the object may change (white dots in right panel)[br] - the horizontal position of the object at those instants of time (lower right panel)[br] - the vertical position of the object at those instants of time (upper right panel)[br][br]A suggested problem -[br][br]Using 4 links, vary x(time) and y(time) so as to make a trajectory in the left [br]panel that is a rhombus.[br][br]Why does the shape of the trajectory not change when you vary the position[br]of the white dots in the right panel? What does change? Why?[br][br][color=#ff0000][i][b]What other problems could/would you pose to your students based on this applet?[/b][/i][/color]