# Wavelength given time, velocity, and cycles

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1. Mar 27, 2015

### GiantSheeps

1. The problem statement, all variables and given/known data
As your hand moves back and forth to generate longitudinal pulses in a spiral spring, your hand completes 2.88 back-and-forth cycles every 6.98 s. The velocity of the pulse in the spring is 0.581 cm/s. What is the wavelength? Answer in units of m.

2. Relevant equations
v=λf
f=1/T

3. The attempt at a solution

First I converted .581 cm/s to .00581 m/s
then I divided 2.88 / 6.98 to get .4126, the period
then I divided 1 / .4126 to get 2.4236, the frequency
and I plugged v and f into the v=λf equation
.00581 / 2.4236 to get .002397 m as the wavelength

but that is incorrect

where did I go wrong? Any help would be greatly appreciated

2. Mar 27, 2015

### T Damen

2.88 cycles in 6.98s = 0.4126 cycles a second is correct.
You state 0.42126 is the period, but does 0.4216 cycles/second really sound like a period to you?

I hope this gets you on the right track cause the rest of your calculations seem valid.
If you still can't get the correct answer let me know!