How to Calculate Mach Speed
What is Mach Speed?
Mach number is the ratio of object speed to the local speed of sound. At sea level (15°C), Mach 1 ≈ 340 m/s (1,225 km/h). The speed of sound decreases with altitude and temperature.
Formula
Step-by-Step Guide
- 1Speed of sound in air = 331.3 × √(1 + T°C/273.15) m/s
- 2Speed = Mach × Speed of sound
- 3Subsonic: < Mach 1; Supersonic: > Mach 1; Hypersonic: > Mach 5
- 4At 11,000m altitude: sound speed ≈ 295 m/s
Worked Examples
Frequently Asked Questions
What is Mach Speed?
Mach number is the ratio of object speed to the local speed of sound. At sea level (15°C), Mach 1 ≈ 340 m/s (1,225 km/h)
How accurate is the Mach Speed calculator?
The calculator uses the standard published formula for mach speed. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Mach Speed calculator use?
This calculator works with inches, kilometres, kilometres per hour, Celsius. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Mach Speed calculator use?
The core formula is: Speed of sound in air = 331.3 × √(1 + T°C/273.15) m/s. Each step in the calculation is shown so you can verify the result manually.
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