Wind speed is determined by
A)direct measurement of the velocity at which air molecules are moving
B)direct measurement of the direction at which air molecules are moving
C)measurements of the effect moving air has on mechanical objects
D)measurements of the effect moving air has on inanimate objects

Question

Quizplus · Accepted Answer

Wind speed is commonly measured by using anemometers, devices that measure the effect of moving air on mechanical objects. The most common type of anemometer measures wind speed by spinning cups or vanes that are attached to a central axis. The speed of the cups or vanes is proportional to the wind speed. Other anemometers use ultrasonic or sonic waves to measure the speed of the wind. These methods all rely on measuring the effect of moving air on a mechanical or ultrasonic device, rather than directly measuring the speed of individual air molecules.

Wind Speed Is Determined by