What is the speed of the waves on the lake?

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SUMMARY

The speed of the waves on the lake is calculated using the relationship between wave frequency and the velocity of the observer. In this scenario, the observer counts three waves every 12 seconds while stationary, yielding a frequency of 0.25 Hz. When moving at 1.50 m/s, the observer counts two waves in the same time frame, resulting in a frequency of 0.17 Hz. The correct application of the formula f' = (1 - v0/v)f0 reveals that the wave speed is 4.8 m/s.

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Homework Statement


While anchored in the middle of a lake, you count exactly three waves hitting your boat every 12.0 s. You raise anchor and start motoring slowly in the same direction the waves are going. When traveling at 1.50 m/s, you notice that exactly two waves are hitting the boat from behind every 12.0 s.

What is the speed of the waves on the lake?

Homework Equations


f+-=(1+-v0/v)f0


The Attempt at a Solution



I have messed up this kind of problem before, so there are many places for me to make mistakes.

3 waves 12 seconds
V= 1.5m/s
2 waves 12 seconds

T1 = 4s
T2 = 6s

f1=.25
f2=.17

.17=(1-v0/1.5).25

.68=1-v0
-.32=-v0/1.5
.48=v0

I know I made a mistake somewhere...
 
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You got the overall idea for the equations but you made a slight mistake...1.5 m/s is the value of Vo (the object's velocity) and v is the velocity of the wave. You mixed the two up.
 


Thank you, that was the mistake.
 

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