Calculating Distance of a Falling Tuning Fork using the Doppler Effect

Click For Summary

Homework Help Overview

The problem involves a tuning fork vibrating at 512Hz that falls from rest under the influence of gravity, with the goal of determining how far it has fallen when sound waves of a different frequency (485Hz) reach the point of release. The context includes the application of the Doppler effect and kinematic equations.

Discussion Character

  • Mixed

Approaches and Questions Raised

  • Participants discuss the application of the Doppler effect equation and kinematic equations to find the distance fallen. There are questions about the calculations and the results obtained, with some participants expressing concern over the accuracy of their answers.

Discussion Status

The discussion is ongoing, with participants sharing their calculations and results. Some guidance has been offered regarding the approach, and there is an acknowledgment of potential rounding errors affecting the outcomes.

Contextual Notes

Participants are working under the constraints of the problem statement and the provided values, including the acceleration due to gravity and the speed of sound in air. There is an indication that assumptions about initial conditions may be under discussion.

Potato-chan
Messages
3
Reaction score
0

Homework Statement


A tuning forking vibrates at 512Hz falls from rest and accelerates at 9.80m/s^2. How far below the point of release is the tuning fork when waves of the frequency 485Hz reach the release point? Take the sound of sound in air to be 340m/s.


Homework Equations


f'=((V+Vo)/(V-Vs))f [doppler effect equ]

Xf=Xi+vt+(1/2)at^2

Vf=Vi+at

The Attempt at a Solution



-Vs = ((V+Vo)f/f')-V

((340+0)512Hz/485)-340

Vs = -18.93 m/s
 
Last edited:
Physics news on Phys.org
The question is asking for the distance the tuning fork has fallen. Have you tried to calculate that yet?
 
Yeah I have but it give me an outragious answer.
 
Like what?
 
So I plug in my found Velocity. into the Vf=Vi+at equation. I know Vi has to be 0 or at least assumed to be. Acceleration is given to me;9.8 m/s^2. and I have the velocity.

Disregarding the sign. 18.93=0+(9.8)t therefore t = 1.93 seconds

Plug that into the distance equation Yf = Yi + vt + .5at^2

Assume Yi = 0

Yf = -18.75

The real answer is suppose to be 19.3
 
Well, I don't think there's an error in your approach. I did get a slightly different answer than you (18.2 m) and I found the distance by a bit more direct method. Maybe rounding error is involved? I don't know.
 

Similar threads

How to find the wavelength of the sound of the tuning fork?
  • · Replies 15 ·
Replies
15
Views
9K
Resonance box with tuning fork, standing wave
  • · Replies 4 ·
Replies
4
Views
3K
Optimizing Resonance Length for Closed-End Pipe with a Tuning Fork
  • · Replies 2 ·
Replies
2
Views
3K
Beats calculation/Doppler Effect
  • · Replies 1 ·
Replies
1
Views
2K
Doppler Effect: Velocity of a train
  • · Replies 4 ·
Replies
4
Views
2K
Doppler effect with frequency ratio
  • · Replies 10 ·
Replies
10
Views
6K
What Is the Correct Water Level for the Third Resonance in a Closed-Open Tube?
  • · Replies 3 ·
Replies
3
Views
4K
How Fast is the Trumpet Player Moving to Create a Beat Frequency of 4 Hz?
  • · Replies 1 ·
Replies
1
Views
2K
How Fast is the Motorcycle in This Doppler Effect Scenario?
  • · Replies 8 ·
Replies
8
Views
2K
How to Calculate Distance Using the Doppler Effect
  • · Replies 1 ·
Replies
1
Views
3K