1. What is the Speed of Sound?

Definition: The speed at which sound waves propagate through a medium, dependent on the medium's properties and temperature.

Purpose: This calculator determines the speed of sound in gases using fundamental thermodynamic properties.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Speed of sound (m/s)
• \( \gamma \) — Adiabatic index (ratio of specific heats)
• \( R \) — Specific gas constant (J/kg·K)
• \( T \) — Absolute temperature (Kelvin)

Explanation: The speed increases with temperature and depends on the gas's molecular properties through γ and R.

3. Importance of Speed of Sound Calculation

Details: Critical for acoustics, aerodynamics, engineering design, and understanding wave propagation in fluids.

4. Using the Calculator

Tips: Enter the adiabatic index (default 1.4 for air), gas constant (default 287 J/kg·K for air), and temperature in Kelvin. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical γ value for air?
A: For dry air at standard conditions, γ ≈ 1.4 (ratio of specific heats at constant pressure and volume).

Q2: How does temperature affect sound speed?
A: Speed increases with the square root of absolute temperature (higher T → faster sound).

Q3: What gas constant should I use?
A: 287 J/kg·K for air, 259.8 for CO₂, 208 for helium - depends on the gas's molecular weight.

Q4: Why absolute temperature (Kelvin)?
A: The formula derives from thermodynamic principles requiring absolute temperature scale.

Q5: Does this work for liquids/solids?
A: No, this formula is for ideal gases. Liquids/solids use bulk modulus/density relations.