Concept explainers
The way that we perceive the temperature on a cold day depends on both air temperature and wind speed. The windchill is what the air temperature would have to be with no wind to achieve the same chilling effect on the skin. In 2002, the National Weather Service issued new windchill temperatures, shown in the table below. (One reason for this new windchill index is that the wind speed is now calculated at 5 feet, the average height of the human body’s face, rather than 33 feet, the height of the standard anemometer, an instrument that calculates wind speed.)
The windchill temperatures shown in the table can be calculated using
in which
a. Rewrite the equation for calculating windchill temperatures using rational exponents.
b. Use the form of the equation in part (a) and a calculator to find the windchill temperature, to the nearest degree, when the air temperature is 25°F and the wind speed is 30 miles per hour.
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Intermediate Algebra for College Students (7th Edition)
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