Please help Speed of sound in air/temperature relation

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SUMMARY

The speed of sound in air can be calculated using the formula \( v = \sqrt{\frac{B}{\rho}} \), where \( B \) is the bulk modulus (1.42 × 105 N/m2) and \( \rho \) is the density (1.211 kg/m3), resulting in a speed of sound of 342.43 m/s. To find the temperature of the air sample, the correct formula is \( v = \sqrt{\frac{1.4 \cdot R \cdot T}{M}} \), where \( R \) is the specific gas constant for air, and \( M \) is the molar mass of air. The user encountered difficulties in calculating the temperature, indicating a potential misunderstanding of the required absolute temperature values.

PREREQUISITES
  • Understanding of the speed of sound formula in gases
  • Knowledge of bulk modulus and density concepts
  • Familiarity with specific gas constants and molar mass of air
  • Basic algebra for manipulating equations
NEXT STEPS
  • Research the specific gas constant for air and its application in sound speed calculations
  • Learn about the relationship between temperature and speed of sound in gases
  • Study the concept of absolute temperature and its importance in thermodynamic equations
  • Practice solving problems involving the speed of sound and temperature in various gases
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Students studying physics or engineering, particularly those focusing on thermodynamics and fluid mechanics, as well as educators seeking to clarify concepts related to sound propagation in gases.

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Homework Statement



The density of a sample of air is 1.211 kg/m3, and the bulk modulus is 1.42 · 105 N/m2.


a) Find the speed of sound in the air sample.


b)Find the temperature of the air sample. Give answer in °C.


Homework Equations





The Attempt at a Solution



I found the part a it's
It's 342.43 m/s
But i find b wrong everytime.What i use is; sqrt[(1.4 x r x T)/M] = speed
But maybe i know the some values wrong? Help please.
 
Physics news on Phys.org
In the calculation, T must be an absolute temperature.

If you show your calculations, it might help us pinpoint what is going wrong.
 

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