Speed of a Wave: Solve for V in 4.6m and 7.4s

  • Thread starter Thread starter pmd28
  • Start date Start date
  • Tags Tags
    Speed Wave
Click For Summary

Homework Help Overview

The problem involves calculating the speed of a wave based on the observed distance between wave crests and the time taken for multiple crests to pass a fixed point. The subject area pertains to wave mechanics.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to calculate the wave speed using the number of crests and the distance between them, but questions arise regarding the interpretation of the timing of the crests. Participants discuss the number of wavelengths between the first and fifth crests.

Discussion Status

Participants are actively engaging in clarifying the setup of the problem, particularly the number of wavelengths involved. Some guidance has been offered regarding the correct interpretation of the timing and the number of wavelengths.

Contextual Notes

The original poster expresses uncertainty about their calculations based on the phrasing of the problem statement, indicating a potential misunderstanding of the timing of the wave crests.

pmd28
Messages
64
Reaction score
0

Homework Statement


A person fishing from a pier observes that five wave crests pass by in 7.4 s and estimates the distance between two successive crests to be 4.6 m. The timing starts with the first crest and ends with the fifth. What is the speed of the wave?



Homework Equations


f=1/T
v=λf

The Attempt at a Solution


I solved for the period first, so in 7.4 sec there was 5 waves. T=1.48
f=1/T=.6757
v=λf=4.6*(.6757)=3.11 m/s

I know my error has to do wit that sentence, "The timing starts with the first crest and ends with the fifth," but I'm not sure what I'm doing wrong.
 
Physics news on Phys.org
Draw a sketch of a wave and number the crests 1 through 5. How many wavelengths are contained between 1 and 5?
 
There are 4 wavelengths.
 
Good. So what should the period T actually be?
 

Similar threads

Equation for the propagation of the crest of a wave
  • · Replies 6 ·
Replies
6
Views
3K
Superposition of two one-dimensional harmonic waves
  • · Replies 10 ·
Replies
10
Views
2K
Calculating Wave Speed: Pier Fishing Observation
  • · Replies 5 ·
Replies
5
Views
7K
Finding amplitude and wave speed in a sinusoidal wave.
  • · Replies 4 ·
Replies
4
Views
3K
Finding Wave Speed: A Boy Fishing on the Jetty
  • · Replies 1 ·
Replies
1
Views
56K
Calculate Speed, Freq & Wavelength of Transverse Waves
  • · Replies 8 ·
Replies
8
Views
31K
Uncertainty in Wavelength Calculation from Wave Crests on a Pier
  • · Replies 6 ·
Replies
6
Views
2K
What Determines the Speed of Waves?
  • · Replies 1 ·
Replies
1
Views
2K
How do you find speed given the beat frequency?
  • · Replies 3 ·
Replies
3
Views
4K
Constructive Interference in Coherent Antenna Arrays
  • · Replies 6 ·
Replies
6
Views
5K