Exploratories

Describing Motion

Problem:

To help students understand and describe the motion of an object. A satisfactory description requires that measurements be made and that the motion be described using equations or graphs.

Materials:

Toys of various types that move such as the following:

Wind-up Walking Toys

Battery Powered Cars

Nerf Dart Gun

Hovercraft

Hot Wheels Car and Launcher

Nerf Ball

Procedure:

1. Have the toys out for students to see.

2. Group students and ask them to experiment with several of the toys, select one, and write a description of its motion.

3. When all groups have written their descriptions, select a student and read a description from one of the other groups. Have the student try to predict the position of the object at some later point in time based on the description.

4. Repeat this with other groups descriptions.

Summing Up:

Students should have the most success with objects that move in a straight line at a constant speed. Suggest that starting a study of motion with this type of motion makes sense. Also point out that it is very difficult to write a good description of motion in words. Suggest

that it is possible to make much more accurate predictions about the motion of an object if information about its position and time are known and presented as a graph or in the form of an equation.