1. Troubleshooting Tips for the Wind Generator Assembly (pages 32-34)

If you are having trouble with the final building project in the manual, please click here for more elaborate instructions, tips, and pictures.

2. Manual Correction on Page 11

The Wind Vane instructions on page 11 of the manual should show that the Wind Vane is to be attached to the small frame with four shaft pins (part 3) rather than four button pins (part 5).

The Wind Vane is used in experiments 1, 2, and 11-17.

3. Manual Correction on Page 18

The power formula shown on page 18 of the first edition manual is incorrect. Here is the correct equation:

ρ is the Greek letter rho, for density. N is power. A is cross-sectional area. v^3 means that the velocity is multiplied by itself three times.

Let’s assume that the wind acts on a windmill that has a blade surface of 1 m^2 with a density of ρ = 1.22 and a velocity of 10 m/s, or 36 km/h (v^3 = 10 x 10 x 10 = 1,000), in which case it would yield a power at the rotor of 0.5 x 1.22 x 1 x 1,000 = 610 watts.