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

[riffwraith]

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?

 

[Wilmer]

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

 

[MarkFL]

The relationship between distance \(d\) traveled, constant velocity \(v\) and time \(t\) may be stated:

\(\displaystyle d=vt\implies t=\frac{d}{v}\)

So, in this problem, we may write:

\(\displaystyle t\approx\frac{8\text{ ft}}{1116.4\dfrac{\text{ft}}{\text{s}}}\approx0.00716589\text{ s}\)