Train Wheel Science

Introduction

Have you ever watched a train roll by? If so, you might have wondered how the train is able to stay on its tracks. The secret lies in the train's wheels. Although they seem cylindrical at first glance, when looking more closely you will notice that they have a slightly semi-conical shape. (Of course, never get close to a working train!) This special geometry is what keeps trains on the tracks. In this activity you will put different wheel shapes to the test to find out why the conical wheel is superior to other designs.

Credits

Materials

• At least four plastic or Styrofoam cups of the same size. (The cups should not have a raised edge at the top.)
• Tape
• Two rulers or yard sticks of the same length
• Book or box
• Flat workspace (that can have items taped to it)
• Flexible cardboard or construction paper (optional)
• Scissors (optional)
• Wooden skewers (optional)