weather [wind] [4] [comprehension quiz]

The speed of air movement and therefore the air speed is measured using a cup anemometer as seen here. The normal unit of wind speed is the knot (nautical mile per hour = 1.15 mph). The Beaufort scale estimates wind strength without the need for instruments and based on the numbers 0 - 17. This first example is: 0: Calm and still winds. Smoke rises vertically. This second example is: 2. Gentle wind at 6-11 kph (4-7 mph). Wind can be felt on face; flags ripple. This third example is: 4. Moderate wind at 20-28 kph (13-18 mph). Paper and leaves scatter. This fourth example is: 6. Strong wind at 39-49 kph (25-31 mph). Umbrellas are hard to use; large tree branches move. This fifth example is: 8. Gale at 62-74 kph (39-46 mph). Twigs and branches break off trees.

1. How many wind speeds are in the Beaufort Scale? 0 17 18 2. Tree branches are breaking, what type of wind is it? moderate gale strong 3. What is the unit of wind speed? knot millibar mph 4. How is the Beaufort Scale a different method? two different instruments together it does't use any instruments the instruments can be carried in a pocket 5. Which instrument measures wind speed? barometer thermometer anemometer

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