A Certain Factory Whistle Can Be Heard Up to a Distance

question 137

Multiple Choice

A certain factory whistle can be heard up to a distance of 9.8 km.Assuming that the acoustic output of the whistle is uniform in all directions,at what distance from the factory is the intensity level of the whistle sound equal to 25 dB? The threshold of human hearing is 1.0 × 10^-12 W/m².

• A)550 m
• B)660 m
• C)830 m
• D)940 m
• E)1,100 m

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Definitions:

Positive Correlation

A relationship between two variables where they move in the same direction, meaning when one variable increases, the other also increases, and vice versa.

Slope

In mathematics, the measure of the steepness or incline of a line, often calculated as the ratio between the change in the y-value to the change in the x-value.

Horizontal Line

In geometry and graphing, a straight line that runs left to right (parallel to the x-axis) and has a slope of zero, indicating no change in the y-value across different points on the line.

Upward-sloping Line

A graphical representation often used to show a positive relationship between two variables on a graph, indicating that as one variable increases, the other does as well.