(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I like to visit reddit. Browsing I found this comic:

I'm assuming sea level.

Speed of sound: 340.29m/s

2. Relevant equations

Wavelength = velocity of wave / frequency

change in frequency = -(velocity source - velocity reciever) / wavelength

(SOURCE: http://en.wikipedia.org/wiki/Doppler_effect)

3. The attempt at a solution

My general method of solving this problem would be to find the wavelength of the raptor's war cry, then once I know that I can figure out how fast the raptor is traveling using the change in frequency formula.

I'm assuming the raptor's war cry is traveling at the speed of sound at sea level:

wavelength = (340.29m/s) / 1260Hz = .27007 m/cycle

Solving for the velocity of the source in the change in frequency equation I get:

-(change in frequency)*(wavelength)+(velocity of receiver) = (velocity of source)

-(60Hz)*.27007m/cycle+9m/s = 7.2m/s

The raptor has a lower velocity than the person, so the raptor will never catch up with him. However, a velocity of a human of 9m/s is Olympic sprinter speed, so am I correct to assume the person will still get eaten because a human can't keep that constant running velocity?

I realize the comic is probably just someone making stuff up without doing the math, so I'm wondering if my solution is correct. I'm pretty sure the math is sound, but without any confidence that the problem is realistic (like the problems I usually encounter) I have no idea if my solution is reasonable.

By the way, this is purely for entertainment purposes. I just enjoy solving stuff like this, it's a nice break from the really hard (and sometimes boring) stuff.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Velocity of a Velociraptor, given frequency of raptor screech. Did I do this right?

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