2 Sound waves reflection easy problems

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Homework Help Overview

The discussion revolves around sound wave reflection problems, specifically questions 21 and 22 related to the timing of sound intervals and the speed of sound in different mediums. Participants are analyzing their interpretations of the problems based on the provided information.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are attempting to calculate time intervals based on clap counts and questioning the number of intervals associated with the claps. There is also discussion about the speed of sound in water versus air and how this affects the answers to the questions.

Discussion Status

The discussion is active, with participants exploring different interpretations of the problems. Some have offered calculations that lead to different conclusions, while others are questioning the assumptions made about the clap counts and the speed of sound. There is no explicit consensus yet, but participants are engaging with each other's reasoning.

Contextual Notes

There is a mention of potential misinterpretation of the questions, particularly regarding how claps are counted, which may affect the calculations. Participants are also considering the implications of sound speed in different mediums on their answers.

Clara Chung
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Homework Statement


Refer to the photos, question 21 and 22(the one with a helicopter)

Homework Equations


Both answers are A

The Attempt at a Solution


for question 21, if the counts to ten, there are 9 intervals. I divide 20 by 9 and divide it again by 2 and get 1.1s not 0.5s.
for question 22. I think it is C. Because the first reflected pulse has traveled 2h and the second reflected pulse has traveled 4h. I think it is impossible for the answer to be A, the pulse should travel slower in water.
 

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For Q21, if the first clap is associated with the count of zero, wouldn't there be 10 intervals?
For Q22, the speed of sound in water is greater than the speed of sound in air.
 
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lewando said:
For Q21, if the first clap is associated with the count of zero, wouldn't there be 10 intervals?
For Q22, the speed of sound in water is greater than the speed of sound in air.
But 20/10(2) = 1s?
 
That is true. That result matches answer B. I can't see how A could be correct.
 
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Actually I misread the question. Only claps are being counted.
 
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lewando said:
Actually I misread the question. Only claps are being counted.
Oh thanks I can do it now
 

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