## Wind

Science, Earth and Space Science

### Objective

1. In this section students make a simple instrument to measure the speed of the wind.
2. use the instrument to record the wind speed over a number of days.
3. construct a simple weather vane to measure wind direction.
4. use the weather vane to record the wind direction over a number of days.
5. investigate how the wind can be put to work.
6. construct a simple machine that is powered by the wind.

### Directions

Measuring the Wind 1 (Page 39)
The pressure of the air on the earth's surface is different in different places. The differences in pressure causes the movement of air or winds. If a pressure difference exists, air moves from the higher pressure to the lower pressure area, in order to even out the pressure. If the high pressure center is close to a low pressure center, the movement from the high pressure to the low pressure is faster and the winds will move faster. The larger the pressure difference, the stronger the winds are. Instruments such as anemometers or wind gauges are used to measure the speed and strength of the wind.
Measuring the Wind 2 (Page 40)
The direction of the wind is determined by the direction the wind is coming from and not the direction it is blowing to. Instruments such as weather vanes and windsocks can measure the direction of the wind.
Wind Power (Page 41)
Using the wind for power is a good idea because it does not cause pollution. In places that are very windy, wind farms are set up where a field full of windmills turn machinery that generates electricity.

### Resources

• pencil or pen
• copies of the activity sheets (see the link below)
• experiment materials as stated on activity pages