MHB If you are 8 ft away from the source, how long does the sound take to reach you?

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The speed of sound is approximately 1116.5 feet per second. To calculate the time it takes for sound to travel 8 feet, the formula used is time equals distance divided by velocity. Applying this, the time is calculated to be approximately 0.00716 seconds. Additional examples provided show that sound takes 0.0716 seconds to travel 80 feet and 7.16 seconds for 8000 feet. The discussion emphasizes the relationship between distance, speed, and time in sound propagation.
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The speed of sound is 761.2 mph, or, according to my math, 1116.5 fps.

If you are 8 ft away from the source, how long does the sound take to reach you?

What is the formula for doing this?

I divided 8 into 1116.5, and got 139.5 - but that doesn't seem to tell me anything. Obviously, the answer is going to be fraction of a second, but is there a real way to figure out what that # is?
 
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1116.5 feet : 1 sec
8 feet : ? sec

1 / 1116.5 * 8 = ~.00716 sec : faster than Superman!

80 feet: .0716 sec
800 feet: .716 sec
8000 feet: 7.16 sec
 
The relationship between distance \(d\) traveled, constant velocity \(v\) and time \(t\) may be stated:

$$d=vt\implies t=\frac{d}{v}$$

So, in this problem, we may write:

$$t\approx\frac{8\text{ ft}}{1116.4\dfrac{\text{ft}}{\text{s}}}\approx0.00716589\text{ s}$$
 
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