Speed of Sound in Air Simulation
This simulation demonstrates how the speed of sound in air varies with temperature, remains independent of pressure, and increases with humidity, according to the formula v = √(γP/ρ).
Temperature
Pressure
Humidity
Current: 20 °C
Speed of Sound:
343.21 m/s
Formula: v = √(γRT/M)
Where γ = 1.4 (adiabatic index), R = 8.314 J/mol·K, M = 0.02897 kg/mol
Current: 101.325 kPa
Speed of Sound:
343.21 m/s (constant)
At constant temperature, speed of sound is independent of pressure because:
From ideal gas law, P/ρ = RT/M = constant when T is constant
Thus v = √(γP/ρ) = √(γRT/M) depends only on temperature
Current: 0 %
Current: 20 °C
Speed of Sound:
343.21 m/s
Humidity increases speed because water vapor (M = 0.018 kg/mol) is lighter than air (M = 0.02897 kg/mol)
Effective molecular weight decreases, increasing speed (v ∝ 1/√M)
Key Formula: v = √(γP/ρ)
Derived Relationships:
- At constant temperature: v = √(γRT/M) → independent of P
- With temperature change: v ∝ √T
- With humidity: v increases as average molecular weight decreases
