How fast do you think the blades on a wind turbine are spinning? Faster than a cheetah? Challenge students to line up (locked arms) in a straight line. One student represents the hub (in the center) and will not move, just pivot. The person at the end of the line represents the tip of the blade and they will be moving quickly. Challenge students to make one rotation as quickly as they can while staying in a straight line! An extension to the activity is to record the time - check out our example "Tip Speed Spreadsheet" below for calculations. Besides a quick and easy way to burn off energy this activity helps students understand that while the turbines appear to be rotating slowly, the tip speed is actually very high.

Materials and Resources:

• Directions Handout
• Optional: Stopwatch and Tape Measure
• Example spreadsheet (Tip Speed) for calculations
• Wind Turbine Comparison Graphics

Image: 2018 Summer STEM Institute